US20090139781A1

US20090139781A1 - Method and apparatus for an electrical vehicle

Info

Publication number: US20090139781A1
Application number: US12/176,005
Authority: US
Inventors: Jeffrey Brian Straubel
Original assignee: Individual
Current assignee: AI Acquisition Corp
Priority date: 2007-07-18
Filing date: 2008-07-18
Publication date: 2009-06-04

Abstract

One embodiment includes a vehicle that includes a battery to supply a flow of electrical energy, an electric motor arranged to propel the vehicle, a first control circuit coupled between the battery and the motor to control the flow of electrical energy to the motor; a first heat exchange loop thermally coupled with a heat exchanger and a heating element, the first heat exchange loop to circulate a first fluid to heat or cool a passenger cabin; a second heat exchange loop thermally coupled with the heat exchanger, the second heat exchange loop to circulate a second fluid to heat or cool the battery and a second control circuit to couple a charger to the battery and to perform charging operations on the battery using a voltage source powered from a line source.

Description

This application claims the benefit of priority under 35 U.S.C. 119(e) to U.S. Provisional Patent Application Ser. No. 60/950,600, filed on Jul. 18, 2007, which is incorporated herein by reference in its entirety.

BACKGROUND

Electric vehicles generally include vehicles that have some device, usually a battery, that stores energy, and that is operable to provide electrical power to one or more systems used, to at least in part, propel or to accelerate the electrical vehicle, or to provide the energy required for some motions of the vehicle. As the stored energy is consumed through either use in the electric vehicle or through some other form of energy dissipation, the source of the stored energy needs to be re-charged in order to replenish the level of stored energy.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram of a bank of batteries according to one embodiment of the present invention.

FIG. 2A is a diagram showing a creation of a mount and a hole in the substrate used to hold the batteries in the bank according to one embodiment of the present invention.

FIG. 2B is a diagram of four mounts in a substrate used to hold batteries in a bank according to one embodiment of the present invention.

FIG. 3 is a side view of batteries in a bank including two substrates and two conductors with electrical connection brackets according to one embodiment of the present invention.

FIG. 4 is a diagram of two conductors with a representative bracket, including an alternate view of the bracket to show its geometry according to one embodiment of the present invention.

FIG. 5 is a side view of five sets of batteries coupled using conductors according to one embodiment of the present invention.

FIG. 6A is a block diagram of the end conductors from two different stacks of multiple sets of batteries and a connector between the stacks according to one embodiment of the present invention.

FIG. 6B is a diagram of a single connector expansion piece according to one embodiment of the present invention.

FIG. 6C is a diagram of a ledge of the connector expansion piece of FIG. 6B showing a nut inserted therein, and a bolt screwed into the nut according to one embodiment of the present invention.

FIG. 7 is a diagram of an expandable connector, including two of the expansion pieces of FIG. 6B according to one embodiment of the present invention.

FIG. 8A is a block diagram of an overhead view of one or more sets of batteries showing the direction of an upper and lower cooling tube coupled to a radiator according to one embodiment of the present invention.

FIG. 8B is a block diagram of an overhead view of one or more sets of batteries showing the direction of an upper and lower cooling tube cooled via a heat exchanger coupled to an air conditioner according to one embodiment of the present invention.

FIG. 8C is a cross sectional view of a structure that contains a pair of tubes according to one embodiment of the present invention.

FIG. 9 is a block diagram of the side view of a row of the sets of batteries illustrating the upper and lower tubes from a different perspective than can be shown in FIG. 8A, according to one embodiment of the present invention.

FIG. 10A is a diagram of a portion of an insert including mounts with integrated air holes according to one embodiment of the present invention.

FIG. 10B is a diagram of a mount being drilled according to one embodiment of the present invention.

FIG. 10C is a diagram of the reverse side of a portion of an insert behind a mount according to one embodiment of the present invention.

FIG. 10D is a diagram of three mounts shown from the side, including a key under the insert according to one embodiment of the present invention.

FIG. 10E is a diagram of two air cooled battery assemblies according to one embodiment of the present invention.

FIG. 10F is a diagram of three air cooled battery assemblies according to one embodiment of the present invention.

FIG. 11 is a diagram of a substrate and walls according to one embodiment of the present invention.

FIG. 12A is a diagram of a substrate, inserts, a cooling tube assembly and walls according to one embodiment of the present invention.

FIG. 12B is an exploded view of a battery assembly, partially filled with two of the dozens of batteries it may contain according to one embodiment of the present invention.

FIG. 13 is a flowchart illustrating a method of assembling substrates, inserts, cooling tubes, walls, batteries, and conductors according to one embodiment of the present invention.

FIG. 14 is a flowchart illustrating a method of mounting batteries in a battery assembly according to one embodiment of the present invention.

FIG. 15 is a flowchart illustrating a method of mounting batteries according to one embodiment of the present invention.

FIG. 16A is a side view of a portion of a battery pack according to one embodiment of the present invention.

FIG. 16B is a top view of the battery pack of FIG. 16A according to one embodiment of the present invention.

FIG. 17 is a block schematic diagram of a set of two battery packs and a fuse according to one embodiment of the present invention.

FIG. 18 is a flowchart illustrating a method of fusibly coupling batteries according to one embodiment of the present invention.

FIG. 19 is a block schematic diagram of a system of parallel-interconnected battery packs according to one embodiment of the present invention.

FIG. 20 is a flowchart illustrating a method of connecting battery packs according to one embodiment of the present invention.

FIG. 21 is a block-schematic diagram of a system of series-interconnected battery packs according to another embodiment of the present invention.

FIGS. 22A and 22B are a diagram of the conductors of each of the two sides of a battery pack according to one embodiment of the present invention.

FIGS. 22C and 22D are a diagram of the conductors of each of the two sides of a battery pack according to another embodiment of the present invention.

FIG. 23 is a block-schematic diagram of a system of series- and parallel-interconnected battery packs according to another embodiment of the present invention.

FIG. 24 is a block schematic diagram of a vehicle containing the set of interconnected battery packs of FIG. 19, 21, 23, or any of these according to one embodiment of the present invention.

FIG. 25A is a diagram of a system of battery cells inhibited from thermal chain reactions according to one embodiment of the present invention.

FIG. 25B is a side view of two of the rows of battery cells in the system of FIG. 25A according to one embodiment of the present invention.

FIG. 25C is a side view of battery cells at least partly surrounded by a thermally-conductive sheet according to one embodiment of the present invention.

FIG. 25D is an overhead view of battery cells at least partly surrounded by a thermally-conductive sheet according to one embodiment of the present invention.

FIG. 26 is a flowchart illustrating a method of manufacturing a chain-reaction-inhibiting battery cell pack and distributing heat generated from one battery cell to several battery cells according to one embodiment of the present invention.

FIG. 27 is a diagram of a conventional vehicle with the battery cell assembly of the present invention.

FIG. 28 is a flowchart illustrating a method of assembling an electric motor rotor according to one embodiment of the present invention.

FIG. 29A is an expanded view of the electric motor rotor according to one embodiment of the present invention.

FIG. 29B is a view of the discs, bars and slugs of the rotor of FIG. 29A wrapped with wires according to another embodiment of the present invention.

FIG. 30 is a cross sectional view of one of the discs in the stack of discs shown in FIGS. 29 and 31 according to one embodiment of the present invention.

FIG. 31 is an exploded view of the electric motor rotor of FIG. 29 according to one embodiment of the present invention.

FIG. 32 is a schematic illustration of a thermal management system in accordance with the invention.

FIG. 33 is a schematic illustration of the primary components of the rotor assembly cooling system;

FIG. 34 is a cross-sectional view of one embodiment of a feed tube support member utilizing a plurality of support spokes;

FIG. 35 is a cross-sectional view of an alternate embodiment of a feed tube support member utilizing a plurality of support spokes coupled to a pair of concentric mounting rings;

FIG. 36 is a cross-sectional view of a perforated feed tube support member;

FIG. 37 is a cross-sectional view of a slotted feed tube support member;

FIG. 38 is an illustration of an alternate rotor assembly cooling system using a helical support strut between the coolant feed tube and the bore of the rotor drive shaft;

FIG. 39 is an illustration of an alternate rotor assembly cooling system using an internally shaped drive shaft; and

FIG. 40 is a conceptual illustration of the rotor assembly cooling system within an electric motor system.

FIG. 41 shows battery cells connected in parallel to form a brick according to the present invention.

FIG. 42 shows bricks of battery cells connected in series to form a sheet according to the present invention.

FIG. 43 shows an architectural representation of an energy storage system (ESS) according to the present invention.

FIG. 44 shows a top view of a battery monitoring board (BMB) according to the present invention.

FIG. 45 shows a perspective view of a battery monitoring board (BMB) according to the present invention.

FIG. 46 shows a flow chart of a methodology of balancing batteries according to the present invention.

FIG. 47 is a schematic view of an electric vehicle communication interface and associated methodology according to the present invention.

FIG. 48 is a flow chart showing the electric vehicle communication interface according to the present invention.

FIG. 49 shows a top view of a battery pack system according to the present invention.

FIG. 50 shows a top view of one battery cell connected to a collector plate via a conductor according to the present invention.

FIG. 51 shows a partial cross sectional view of a battery pack system according to the present invention.

FIG. 52 shows a top view of a battery cell according to the present invention

FIG. 53 shows a side view of an apparatus for deactivating bad battery cells according to the present invention.

FIG. 54 shows a top view of an apparatus for deactivating bad battery cells according to the present invention.

FIG. 55 shows a flow chart of one methodology of deactivating faulty or bad battery cells according to the present invention.

FIG. 56 shows a view of a sheet which is a subsystem of an energy storage system (ESS) according to the present invention.

FIG. 57 shows a view of an energy storage system enclosure according to the present invention.

FIG. 58 shows thermistors attached to six different cells of the energy storage system according to the present invention.

FIG. 59 shows a view of a manifold according to the present invention.

FIG. 60 shows a side view of a cooling tube according to the present invention.

FIG. 61 shows an end view of a cooling tube arranged within a tube seal plug according to the present invention.

FIG. 62 shows a side view of a cooling tube according to the present invention.

FIG. 63 shows a top view of a cooling tube inter-engaged with cells of a sheet of an energy storage system according to the present invention.

FIG. 64 shows a view of the end fittings arranged over an end of a cooling tube according to the present invention.

FIG. 65 shows the connection of a manifold and tube seal plug to an ESS enclosure according to the present invention.

FIG. 66 shows the counter flow architecture of the thermal management system according to the present invention.

FIG. 67 shows an energy storage system according to the present invention.

FIG. 68 shows a battery module or sheet having an electrical pyrometer therein according to the present invention.

FIG. 69 shows a view of a battery module in infrared showing the infrared photons from one hot cell reflecting throughout the module.

FIG. 70 shows a radiation energy density diagram within a battery module for normal and hot cell conditions.

FIG. 71 shows a battery module according to the present invention having an optical pyrometer arranged therein and at least one reflective surface arranged therein.

FIG. 72 shows a manifold connected to an energy storage system (ESS) enclosure according to the present invention.

FIG. 73 shows an energy storage system according to the present invention.

FIGS. 74 A and B shows a top view of a cooling tube having an optimized geometry according to the present invention.

FIG. 75 A-D shows a perspective view, a top view, an end view and a side view of a scalloped cooling tube for use in a thermal management system according to the present invention.

FIG. 76 shows a perspective view of a scalloped cooling tube according to the present invention.

FIG. 77 shows a close up view of a scalloped cooling tube according to the present invention.

FIG. 78 shows a scalloped cooling tube arranged between adjacent rows of cells according to the present invention.

FIG. 79 shows a compressible thermal pad for use with a cooling tube according to the present invention.

FIG. 80 shows a die used to create a scalloped cooling tube according to the present invention.

FIG. 81 shows an alternate embodiment of a die used to make a scalloped cooling tube according to the present invention.

FIG. 82 shows a thermally conductive compound used to fill space between the cells in a battery pack.

FIG. 83 shows an aluminum cooling tube potted in with the cells of a battery pack.

FIG. 84 A-B show metal collector plates arranged on each end of the cells of a battery pack.

FIG. 85 shows the cells arranged in an array in space.

FIG. 86 shows normal operating cells oriented transversely relative to a hot cell in the middle.

FIG. 87 shows normal cells oriented axially relative to a hot cell in the middle.

FIG. 88 shows an insulator arranged around each end of a plurality of cells of a battery pack.

FIG. 89 shows a diagram of a system for mitigation of propagation of a thermal runaway event within an energy storage system according to the present invention.

FIG. 90 is a schematic view of an electric vehicle communication interface and associated methodology according to the present invention.

FIG. 91 is a flow chart showing the electric vehicle communication interface according to the present invention.

FIG. 92 shows a vehicle system to various embodiments of the present subject matter;

FIG. 93A shows a functional block diagram of a charging system 200Q for a battery pack 252Q according to various embodiments of the present subject matter;

FIG. 93.B shows a charging circuit according to various embodiments of the present subject matter;

FIG. 93C shows a charging circuit according to various embodiments of the present subject matter;

FIG. 94 shows a charging station according to various embodiments of the present subject matter;

FIG. 95A shows a graph including a voltage waveform according to various embodiments of the present subject matter;

FIG. 95B shows a graph 450Q of a voltage level for a battery pack during a charging operation according to various embodiments of the present subject matter;

FIG. 96 shows a flowchart for one or more methods according to various embodiments of the present subject matter.

FIG. 97A shows diagrams of voltage levels according to various embodiments of the present subject matter;

FIG. 97B shows diagrams of voltage levels according to various embodiments of the present subject matter.

FIG. 98 is a high level diagram of an electric vehicle, according to one embodiment.

FIG. 99 is a partial perspective view of a clamshell, according to one embodiment.

FIG. 100 is a cross section taken along line 3-3 in FIG. 2.

FIG. 101 is a cross section taken along line 4-4 in FIG. 2.

FIG. 102 is a partial perspective view of a clamshell including a protrusion, according to one embodiment.

FIG. 103 is a cross section taken along line 6-6, according to one embodiment.

FIG. 104 is a process according to one embodiment.

FIG. 105 is a high level diagram of an electric vehicle, according to one embodiment.

FIG. 106 is a diagram of an electrical vehicle charging system, according to one embodiment.

FIG. 107 is a block diagram of an article according to various embodiments of the invention.

FIG. 108 is a method of charging a battery, according to one embodiment of the present subject matter.

FIG. 109 is a method of charging a battery to a first energy stored level during a first time period and charging the battery during a second time period, according to one embodiment of the present subject matter.

FIG. 110 is a method of charging a battery during a second time period, according to one embodiment of the present subject matter.

FIG. 111 is a method of charging to a first energy stored level during a first time period, and to a second energy stored level during a second time period, according to one embodiment of the present subject matter.

FIG. 112 is a method of charging a battery in the context of a charging rate that varies up and down throughout the day, according to one embodiment of the present subject matter.

FIG. 113 is a method according to one embodiment of the present subject matter.

FIG. 114 is a method of charging a battery to achieve a selected range, according to one embodiment of the present subject matter.

FIG. 115 is a high level diagram of an electric vehicle with a battery and a charging indicator, according to one embodiment of the present subject matter.

FIG. 116 shows a vehicle system, according to one embodiment of the present subject matter.

FIG. 117 illustrates a partial perspective view of a system including an electric vehicle, a charger, a charging coupler port, and other components, according to one embodiment.

FIG. 118 illustrates a cross section along line 4-4 in FIG. 117.

FIG. 119 illustrates a perspective view of a charging coupler port, according to one embodiment.

FIG. 120 illustrates a process for indicating charge, according to one embodiment.

FIG. 121 shows a vehicle system according to one embodiment of the present subject matter.

FIG. 122 is a block diagram of a system for cooling a battery and cabin according to various embodiments;

FIG. 123 is a block diagram of a system for cooling multiple zones according to various embodiments;

FIG. 124 is a flow diagram illustrating a method for cooling a battery according to various embodiments;

FIG. 125 is a flow diagram illustrating another method for cooling a battery according to various embodiments;

FIG. 126 is a block diagram of an example system according to some embodiments.

DETAILED DESCRIPTION

In the following description, reference is made to the accompanying drawings that form a part hereof, and in which is shown by way of illustration specific embodiments which may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention, and it is to be understood that other embodiments may be utilized and that structural, logical and electrical changes may be made without departing from the scope of the present invention. The following description of example embodiments is, therefore, not to be taken in a limited sense, and the scope of the present invention is defined by the appended claims.
Referring now to FIG. 1, a substrate used to hold one or more sets of one or more batteries is shown according to one embodiment of the present invention. The batteries used in one embodiment are any conventional rechargeable batteries having an 18650 form factor, but other types of batteries and other form factors may be used.
The substrate 112 may be made of a material that electrically insulates one face of the substrate from the other face. The substrate 112 has at least two faces and may or may not be substantially flat. In one embodiment, the substrate 112 has two primary faces, both of which are made of an electrically insulating material. In one embodiment, the substrate is a single layer of such insulating material, such as fiberglass or plastic, and in another embodiment, one or more layers of a conducting material are formed in the substrate in the manner of a conventional printed circuit board to allow wiring for sensors to be run along as part of the substrate.
The substrate 112 may be cut or formed into a shape that matches or somewhat matches two of the dimensions of a space available for batteries. As shown in the figure, the substrate 112 has an irregular shape, but regular shapes (e.g. a triangle or square) may also be used. This can allow a higher number of batteries to occupy the space available for such batteries than would be possible if the substrate 112 shape did not match the space available. Although the shape of the substrate 112 can help to maximize the number of batteries that can fit into a space, as noted below, in one embodiment, the batteries are not so tightly packed as to have the sides of each battery touching one another, but instead are spaced from one another to allow for cooling and to allow for dimensional tolerance of the batteries. In one embodiment, the batteries are spaced to allow for cooling of the batteries, either by air cooling or cooling via tubes running between the batteries as described in more detail below.
In one embodiment, the substrate 112 has a substantially flat shape. In one embodiment, the substrate 112 is a ⅜ inch thick fiberglass sheet, however, as described below, injection-molded plastic may be used, as well as other substrates. Any electrically-insulating material may be used for a substrate 112.
In one embodiment, the substrate is substantially rigid, to allow it to distribute force applied to one portion of the substrate among a wider area. As noted below, batteries are sandwiched between two substrates, and if the substrate is rigid, a force applied perpendicularly to the surface of the substrate 112 external to that of the batteries, will be distributed by the substrate 112 across two or three or four or five or more of the batteries and potentially many more. As noted below, the force may also be applied to spacers, walls or other structured components of the finished assembly. Thus, each of the batteries will be required to withstand only a fraction of the force, making it less likely that the force will crush any battery. In one embodiment, dozens of batteries and spacers and/or walls are sandwiched between a substrate that is sufficiently thick to distribute a force across many of the batteries, making it extremely resistant to crushing. As described below, spacers, walls, or both may be sandwiched between the substrate in addition to the batteries, either near the sides of the substrate or interior thereto or both, and if the spacers or walls have a crushing strength greater than the batteries, the spacers and/or walls add additional crush strength to the sandwich of batteries and substrate.
In one embodiment, each substrate 112 has a mount 110 for the insertion of each battery held by the substrate. In one embodiment, there are multiple mounts on the substrate, allowing a substrate to hold multiple batteries. The mount 110 may be raised from the substrate 112 or recessed into it or both. Batteries are inserted into mounts 110, which are milled, molded or otherwise formed in the substrate 112 or, as noted below, the mounts may be milled, molded or otherwise formed into an insert to the substrate 112.
In one embodiment, mount 110 is a well, and such embodiment will now be described, although the description of how the well is used is applicable to any form of mount 110. In one embodiment, the well extents from one surface of the substrate, part way into the substrate 112. For example, for a ⅜ inch substrate, the well may be ¼ inch deep. The well may be shaped so that it holds the end of the battery when a battery is pressed into it. In one embodiment, a well is formed as will now be described with reference to FIG. 2A, which shows the various positions of a milling tool used to mill each well in the substrate.
Each well 200 will hold one of the two ends of each battery to be mounted in the substrate. Referring now to FIG. 2A, a well 200 is shown according to one embodiment of the present invention. In one embodiment, a well 200 is milled using an 11/16 inch mill bit. The end of the bit is brought into contact with the surface of the substrate 112 to drill a pilot hole 210 part way through the substrate, for example ¼ inch deep in a substrate that is thicker than ¼ of an inch. The bit is then moved sideways 12/1000 of an inch from the pilot hole in three or more directions, so as to form “petals” extending from the pilot hole 210. As shown in the figure, four directions are used to make four petals, with the bit being brought to position 212, then to position 214, then back to the position of the pilot hole 210, and, from the position of the pilot hole, to position 216 and then to position 218. The bit is moved 12/1000 of an inch from the pilot hole center for each of the four directions. The resulting hole is slightly smaller than the battery at several points 222, 224, 226, 228, such points being referred to as “teeth”. Teeth 222, 224, 226, 228 are thin (e.g. they have about the same or a smaller cross section than the thickness of the substrate that comes in contact with the battery when mounted) or narrow areas of substrate 112 that contact the battery inserted in the mount and hold it at modest to high force per square inch as compared with the other edges of the well 200, which may not contact the battery at all. The force may be at least large enough so that a battery will not wobble or fall over when inserted into the mount. The teeth 222, 224, 226, 228 may slightly deform when a battery is inserted into the well, allowing the teeth 222, 224, 226, 228 to hold the battery in place when the battery is inserted.
A hole 230 is then drilled from either direction all the way through the substrate 112. In one embodiment, hole 230 is centered at the pilot hole of the well 200, and has a diameter approximately equal to, or slightly smaller than, the diameter of the positive button terminal of the battery. In this arrangement, substrate 212 will protect the negative body of the battery from being shorted to the positive terminal in the event that a conductor in contact with the positive terminal of the battery near the face of the substrate 112 outside of the face holding the battery is pushed towards the batteries. The hole 230 will allow electrical connection to the terminals of the battery as described in more detail below. Hole 230 is not considered part of the well 200 or other mount in one embodiment, and in another embodiment, it is.
There are other ways of providing a mount 110 and hole for each end of each battery held by substrate 112. Referring now to FIG. 2B an alternate manner of providing a mount 110 and a hole in substrate 112 is shown. In this embodiment, substrate 112 may be molded from conventional plastic, such as by using conventional injection molding techniques. Substrate 112 is shown with four wells 240 used to hold the ends of each of four batteries (not shown). Although four wells 240 are shown in one embodiment, there may be any number of wells 240. The wells 240 are areas of the substrate 112 that are thinner than other areas of the substrate 112, for example, if the substrate between the wells is generally ½″ thick plastic, the wells may be formed so that the thickness of the plastic is ⅛″ within the well. The side of the substrate 112 opposite the well 240 may be completely flush with the remainder of the substrate. The well 240 forms a depression in the substrate 112 to admit one end of the battery. Each well may have a substantially circular shape, though other shapes may be used. Each well 240 has several fins 244 to hold the battery, the fins 244 having a relatively narrow thickness, such that they can deform when a battery is inserted into the well and operate like the teeth described above. The circular area 246 exposed by the fins 244 is slightly less than the cross section of the end of the battery being inserted, and in one embodiment, the areas 246 may be slightly smaller or larger based on the polarity of the battery end being inserted. A hole 242 is formed or drilled in the substrate 112 to allow electrical connection to the batteries, and serves the same purpose and has the same geometry relative to the well 240 as hole 230 had relative to well 200.
The holes are shown herein as being round, but holes may have any shape. Holes and the elements that hold the batteries may be any shape.
Referring now to FIG. 3, a cross section of a substrate 112 of FIG. 1, and another substrate 320 sandwiching batteries 310, 312 is shown according to one embodiment of the present invention. In one embodiment, substrate 320 is a mirror image of substrate 112 described above, and otherwise is of similar or identical manufacture as substrate 112.
Batteries 310, 312 are inserted into one substrate 320, and then a press may be used to press the opposite substrate 112 onto the other end of the batteries. As noted below, spacers such as spacer 364 may be inserted into spacer wells 360 in substrate 320 before substrate 112 is pressed onto batteries 310, 312 to allow spacer 364 to be a part of the structure containing batteries 310, 312, spacers 364 and substrates 112, 320. Spacer 364 provides added crush strength to the structure formed by the batteries 310, 312 and the substrates 112, 320, and the screws or other fasteners (not shown) that may connect the substrates 112, 320 to the spacer 364 via hole 362 (and the opposite hole in substrate 112) provide a clamping force to hold the substrates 112, 320 more securely against the batteries 310, 312.
Although only two batteries are shown in the Figure, any number of batteries may be employed in a similar fashion. Although only one spacer 364 is shown, any number may be used at the periphery of the substrates 112, 320, interior thereto, or any of these locations.
Hole 230 and similar hole 344 in the substrates 112, 320 permit electrical connection to battery 310, and other similar holes on either end of other batteries, permit electrical connection between the terminals 314, 316 of the batteries 310, 312 and two different conductors 340, 350. In one embodiment, conductors 340, 350 are made of a conducting material such as copper or copper plated metal and have the shape of plates. In one embodiment, the plates are rigid, having a thickness in excess of approximately 20/1000 of an inch. In each conductor 340, 350 are holes 346, 356 placed so that the holes 346, 356 will be approximately at the location of the battery terminals 314, 316 when the conductors 340, 350 are mounted to the substrates 112, 320. The conductors 340, 350 may be mounted using spacers to hold the conductors 340, 350 slightly off of the substrates 112, 320, just outside of the area in which the battery is sandwiched, or the conductors 340, 350 may be attached directly to, on the face outside of, their respective substrates 112, 320. Conductors 340, 350 may be glued to the substrates or may be held down by the welds to the batteries as described below. In one embodiment, conductors 340, 350 are a part of the substrates 112, 320 themselves, in the manner of a printed circuit board.
In one embodiment, the conductors 340, 350 have attached thereto, brackets 342, 352 made of a conducting material, such as tin, nickel or copper. In one embodiment, there is one bracket 342, 352 attached to the conductor 340, 350 per battery 310, 312 that is or will be electrically connected to the conductor 340, 350, although other embodiments employ multiple brackets as a single strip. In one embodiment, before attaching the conductors to the batteries 310, 312, the bracket 342, 352 is inserted into a hole 346, 356 in the conductor 340, 350. In one embodiment, in each conductor 340, 350, there is one hole 346, 356 and one bracket 342, 352 per battery that a conductor 340, 350 will contact. When all of the brackets 342 of a conductor 340 have been inserted into the holes of that conductor 340, the brackets are then wave soldered, welded, infrared reflow soldered or otherwise electrically connected to the conductor 340, thereby forming an electrical connection between the brackets 340 and the conductor 342. Other methods of electrically connecting the brackets 342 of a conductor 340 and the conductor 340 may be employed. In one embodiment, the holes 346, 356 in the conductors 340, 350 are on the same centers as, but smaller than, the holes 230, 344 in substrates 112, 320.
A representative bracket 342 and conductor 340 are shown from a different angle in FIG. 4. As can be seen in FIGS. 3 and 4, brackets, such as bracket 342 have a substantially U shape with the ends bent outward so that they can be inserted into the holes such as hole 346, one bracket per hole. Each bracket may be made of a shape, material or both to allow it to have at least a slight give, to allow the brackets 342 to compensate for variation in battery placement within the mounts and the substrate and optionally, the inserts used to mount the batteries as described herein. In one embodiment, each bracket, or multiple portions of a strip, has a shape substantially as shown in the expanded view of FIG. 4 that allows for a spring action to accommodate variations in lengths of the batteries and tolerances in substrates, mounts, and the like. Bends forming the surfaces 420 provide the spring action, with the distance d between the underside of the topmost horizontal surface and the underside of the bottommost horizontal surface at least as large as the maximum expected distance between the outside of the conductor 340 and the edge of the any terminal of any of the batteries. Stiffeners 422 are a bent piece of the bracket 342 that helps keep the lowermost horizontal surface substantially flat. The geometry and dimensions of the bracket 342 may be arranged to ensure that if it is crushed into the positive terminal, it does not splay into the negative case of the battery, but instead, side surfaces compress inwards.
Although only one bracket is shown in the Figure, each hole shown may have a bracket inserted in the same manner as is shown and wave soldered to each conductor 340, 412 in one embodiment. In one embodiment, a single bracket 348 in the shape of multiple end-to-end brackets 342 spans multiple holes, to reduce the manufacturing costs of installing multiple brackets.
The holes such as hole 346 are positioned to have the same spacing as the batteries 310, 312 over which they will be positioned so that when a conductor such as conductor 340 is placed into position above or below a set of batteries, that each of the brackets for that conductor will contact a terminal 314 or 316 of a different one of the batteries in the set or sets of batteries to which the conductor 340 is in physical and electrical contact.
The conductors 340, 350 may be mounted to the substrate 112 or 320 so that each of at least one of the brackets 342, 352 are in contact with at least one terminal 314 or 316 of a battery 310, 312 mounted or to be mounted in substrate 112 and 320. In one embodiment, the distance d of bracket 342 is such that it will extend through the hole 346 in the conductor 340 and the hole in the substrate 320 and any space between the conductor 340 and the substrate 320 and contact a battery 310, 312, even if the battery 310, 312 is not fully seated into its mount. Bracket 352 is similarly or identically sized for its conductor 350, substrate 112 and any spacing between the two.
In one embodiment, each bracket 342, 352 may then be physically attached, such as via a weld from a spot welder or laser, to the terminal 314, 316 to which it is connected.
Spacer well 360 admits a metal or plastic spacer 364 with optional holes drilled into both ends of (and optionally, all the way through) the spacer 364 to admit a screw (not shown) to be inserted into hole 362 from under substrate 320 and screwed into the spacer 364. Another screw may be screwed into the other end of spacer 364 from above substrate 112. Spacers may be positioned along the periphery of the substrates 320, 112 or interior thereto or both types of positions of spacers may be used.
In one embodiment, the batteries 310, 312 are arranged in sets of one or more batteries 310, 312, with all of the batteries in the same set being oriented with the same polarity in one direction, and all of the batteries in the set having their terminals 314, 316 electrically connected by, and physically in contact with, the same conductor 340, 350, although, as noted below, a conductor 340, 350 may be in electrical and physical contact with at least one other set of batteries, oriented with the opposite polarity as the first set, thus forming a series connection between the sets.
Conductors 340, 350 are used to connect the set of batteries 310, 312 in contact with the brackets in parallel with the other batteries of the set, and optionally in series with another set. This may be accomplished by inverting the batteries in an adjacent set and using a single conductor 340, 350 to connect all of the batteries at one end of each set. When this arrangement is used, the batteries in the first set are connected in parallel with each other, as well as in series with the other set. Adjacent sets of batteries may be alternately positioned, with a conductor 340, 350 spanning both sets of batteries on one side, though all the batteries in one set will contact the same conductor with a different polarity from all the batteries in the other set.
As noted above, batteries, spacers or both may be the primary means of connecting and supporting substrates. However, in another embodiment, perimeter and divider walls are used as one method or the primary method to connect and support the substrates. Referring now to FIG. 11, the substrate shown in FIG. 1 is shown with perimeter and divider walls according to one embodiment of the present invention. A perimeter wall 1110 is attached to substrate 1112. Attachment may be made by means of glue, heat bonding or melting of the wall 1110 to the substrate, or conventional snap together methods or other fasteners via fasteners 1114. Perimeter wall 1110 may be made of several pieces, with edge or corner connectors connecting each of the pieces. Perimeter wall 1110 may contain connectors such as connector 1116, which may be a slot or other fastener molded into the perimeter wall 1110. Connector 1116 attaches to a divider wall 1118, which may be attached to the substrate 1112 in the same manner as perimeter wall 1110. As shown in the figure, divider walls such as divider wall 1118 may itself have connectors that hold up still other divider walls.
In one embodiment, perimeter walls 1110 are used to physically protect batteries from outside intrusion, and divider walls 1118 are used to protect batteries, that may be pushed via an unwanted external force, from pushing other batteries nearby, and may also confine any unwanted thermal reactions to a subset of the batteries bounded by one set of walls 1110 or 1118. In addition, because the side walls of the batteries are connected to the negative terminal, and negative terminals of adjacent batteries may be at different potentials from one another, the use of divider walls 1118 can help prevent short circuits that would otherwise occur if the batteries, having different electrical potentials of their respective cases were to touch cases due to an unwanted force. In one embodiment, either a divider wall or a cooling tube (described below) is used to separate adjacent batteries having negative terminals and cases at differing potentials.
FIG. 5 shows 5 batteries 500-508 connected in series to increase the voltage to approximately five times the voltage of one battery via conductors 520-530 using the techniques of the present invention (the substrates, brackets, and spacers have been omitted from the Figure to improve the clarity of the Figure). Although there is only one battery 500-508 in each set in FIG. 5, more than one battery per set connected to the same pair of conductors 520-530 and using the same polarity as each battery 500-508 shown could have been used to increase the current to an approximate multiple of the current of the single battery 500-508. In one embodiment, end conductors 520, 530 have terminals 540, 542, which may be screw terminals or an embedded screw post with a nut that is screwed over the screw post. A wire may be attached to each terminal 540, 542 in a conventional manner to allow power from the battery to be brought to a point of use. The point of use may be an electric motor in an electric car in one embodiment of the present invention, and there may be more than one terminal 540, 542 per end conductor 520, 530, such as is described below. It is noted that in the Figure, conductors 520-530 collectively contact all of the batteries from which current through each conductor 520-530 is provided, but individually, the conductors 520-530 do not contact all of the batteries 500-508 and each conductor 520-530 is at a different electrical potential from the others relative to any other one of the conductors 520-530.
As shown in the Figure, an odd number of sets of batteries (in the Figure, there is one battery per set) will cause the end conductors 520, 530 to be located on opposite sides of the batteries 500-508. Having an odd number of sets, where the sets are connected to one another in series as shown, can produce a useful assembly 500 of batteries 500-508 because the assemblies themselves can be coupled in series with a minimum of interconnection. If the sets of batteries are arranged in a pattern that causes the first set and the last set to be near each other (such as if the sets are arranged in a somewhat circular pattern around the assembly, the end conductors can be on opposite sides of the assembly, in the same general region, but without significant cross connection structures, allowing interconnection of assemblies with a minimum of cross connection runs.
The batteries sandwiched by substrates and inserts and connected by conductors as described herein may have insulating paper or other insulating material attached thereto, and multiple such assemblies or structures of batteries may be electrically interconnected. FIG. 6A illustrates the end conductors 636, 637 of two different structures, similar to the end conductors 530, 520 of FIG. 5, each coupled to one or more sets of batteries arranged as described above with respect to FIGS. 1-5, with the detail showing the batteries, substrates, remaining conductors and other structures omitted in the Figure to show the interconnections between end conductors of two different structures (the word structure and assembly are used interchangeably herein). End conductor 636 is an end conductor of one structure, and end conductor 637 is an end conductor of another structure, with the structures intended to be electrically connected in series to one another using expandable connector 650.
Referring now to FIG. 6A, end conductors 636, 637 have a portion rising above the substrate sandwiched between the end conductors 636, 637 and the batteries to which the end conductors 636, 637 are coupled, such portion being illustrated above the dashed line in the Figure, said line representing the top of the substrate. In one embodiment, U-shaped holes 634 are milled into, or formed as part of, the end conductors 636, 637 to allow insertion of terminals 638 of a connector 650 to be inserted therein, when the connector 650 is inserted in the direction of the arrow. Terminals on the opposite side of expandable connector 650 are not visible, but are the same in number as the visible side, and offset from those on the visible side. In one embodiment, there are more U-shaped holes 634 than terminals 638 on one side of the expandable connector 650 to allow each end conductor 636, 637 to operate on either side of connector 650. Terminals 638, which may be bolts or screws are then tightened over the end conductors 636, 637 to cause a connection between the end conductors 636, 637 and an expandable conductor 640 made of copper or another conducting material. Expandable conductor 650 is a flat conductor bent in a U cross section, and flexible enough to expand when terminals 638 are tightened.
Expandable connector 650 is shown in greater detail in FIG. 6D. Referring now to FIG. 6D, expandable connector 640 has three primary sets components. There are two expansion pieces 610, one expandable conductor 640 and six terminals 638, though other numbers of terminals may be used.
Expansion pieces 610 are shown in greater detail in FIG. 6B. Referring now to FIG. 6B, one embodiment, expansion piece 610 has multiple ledges 616, each ledge 616 containing a recessed well 612 that holds a nut and prevents it from turning, and may be a tight enough fit to hold the nut in place in the well 612. The well 612 is about as deep as the nut is thick. Each well 612 has a hole drilled or formed into the center of the well and extending straight through to the opposite side of the ledge 616. FIG. 6B shows a ledge in greater detail. A nut 630 has been inserted into the well and a bolt 632 has been inserted from the opposite side of the ledge 616 from the side from which the nut was inserted 630 through the hole in the well and threaded into the nut 630. As noted below, in practice, the nut will be inserted through a hole in the expansion conductor 640, which is not shown in FIG. 6B.
Referring now to FIGS. 6B-6D, to assemble the expandable connector two expansion pieces 610 are mated together, facing one another so that their ledges 616 are in a single plane, but having their wells facing 180 degrees away from one another. The expansion conductor 640 is slipped over the ledges 616 and bolts or screws are inserted through holes in the expansion conductor and through a hole 614 in the ledge 616 until they reach the nuts 630 at the opposite side of the ledge 616, and are screwed part way into the nuts 630. Referring momentarily to FIG. 6A, the expansion connector 650 is slipped between two end conductors as shown in FIG. 6A, and the screws or nuts 632 are tightened.
When the screws or bolts 632 are tightened, they pull the ledges 616 of the expansion connectors 610 apart from one another in opposite directions, with the face of the ledge opposite the well 612 pressing against the nearby area of the expansion conductor 640 to press it into contact with the edge connector 636, 637, providing an electrical connection that can carry significant current and is physically stable, yet can be disassembled and reassembled as necessary.
Expandable conductor 650 is described herein as connecting two structures in series. However, expandable conductor may be used to connect multiple structures in parallel as well.
In one embodiment, the batteries may be liquid cooled via small, thermally conductive tubes through which water or another coolant, such as any conventional anti-freeze mixed with water, oil, or even cold air, may be circulated via conventional means such as a pump.
The tubes absorb heat from the batteries and transfer it to the liquid, coolant or air. The pump may pump the liquid to a radiator where the heat is released to the air near the radiator, or to a heat exchanger that exchanges heat with a refrigerant, such as conventional R-134a, that operates as part of a conventional heat pump, which absorbs heat from the coolant or other liquid and releases it to a radiator. In the event that the batteries are powering an electric car, the radiator may be drawn through the ambient air when the car is in motion to enable additional heat to be released into the air.
FIGS. 8A and 9 illustrate the coolant-containing tube, from different perspectives: FIG. 8A is a top view and FIG. 9 is a side view of a different set containing a different number of batteries, but is similar to what would be seen by looking from the third row of batteries from the top of FIG. 8A towards the second row of batteries from the top of FIG. 8 to show the detail not visible in FIG. 8A. FIG. 9 is actually superimposed onto the batteries shown FIG. 5. In one embodiment, one tube 810 is arranged to run near each battery (the position of each battery will roughly correspond to the circles of FIG. 8A) in one or more sets. Referring now to FIGS. 8A and 9, in one embodiment, the tube has an inlet 812 for accepting the liquid, which runs near each of the batteries that it will cool, and then, in one embodiment, the tube turns around via a turnaround section 910 shown in FIG. 9 and runs past each battery a second time, either on the same side of the battery as the first run, or on the opposite side. The turnaround section 910 may be outside of the substrate, for example, near inlet 812, to avoid a joint (between turnaround section 910 and the remainder of the tube 810) being near the batteries. Conventional heat conductive, but not electrically conductive, potting compound (not shown) or another heat conductive substance, such as KONA 8701-LV-DP heat conductive compound commercially available from Resin Technology Group, LLC, may be poured over the tubes so that it also touches the batteries and helps conduct heat from the batteries to the tubes.
The direction of flow of the coolant in the tubes is shown by the arrows in FIG. 9. An outlet (directly over the inlet 812 in one embodiment) exhausts the coolant to the radiator 814 where the coolant releases its heat, with the coolant being circulated by pump 820. Because two runs of the tube are used near each battery, with the flow of coolant in the tubes running past each battery being in opposite directions and in the opposite order, the batteries may be cooled more evenly than if a single run were employed. In one embodiment, the two tubes are actually part of a single structure, to allow the heat from the two tubes to be exchanged, further stabilizing the temperature of the coolant in the tubes across the run of the tubes. Referring now to FIG. 8C, a single structure 860 containing two tubes is shown according to one embodiment of the present invention. The structure 860 contains crosspiece 864, and may be formed as part of a single extruded piece of aluminum or another heat-conductive material. The crosspiece 864 and structure 860 form the two tubes 862, 866 having opposite directions of flow. In one embodiment, the top tube 862 is coupled to the inlet and in another embodiment, the top tube 862 is coupled to the outlet, though other embodiments may reverse those connections.
In one embodiment, the outer surfaces of the tubes are made of an electrically insulating material so as not to cause shorts between the cases of the batteries, which are electrically connected to the negative battery terminal. Because the negative terminals of different batteries are at different electrical potentials, if the tube touches the batteries, a short could occur if a tube were made of an electrically conductive material. In one embodiment, the tubes are made of aluminum and the outer portion is anodized to cause the outer edges of the aluminum to be a poor conductor.
In one embodiment, instead of a radiator absorbing the heat from the tubes and their contents, in the case of an at least partially electric-powered car or other vehicle, heat from the tubes and their contents may be absorbed by an evaporator in a conventional air conditioning system. Referring now to FIG. 8B, a system for cooling batteries is shown according to one embodiment of the present invention. Elements 810-820 operate as described in FIG. 8B above, except that instead of releasing heat to a radiator 814, heat from the batteries absorbed by the coolant in the tubes is released to a conventional evaporator 834 in a heat exchanger 836. Compressor 830 compresses a refrigerant and provides it to a condenser 840, which may be placed near a fan 842 or other airflow. The refrigerant arrives into an accumulator and is provided to the evaporator 834 and returned to compressor 830. A heat exchanger 836 allows the evaporator 834 to absorb heat from the tubes, after the coolant has passed by some or all of the batteries. In one embodiment, a single compressor is used to not only cool the batteries, but also the air in the passenger compartment. A second evaporator 844 absorbs heat in air provided to the passenger compartment via a blower 846 and the refrigerant then collects in the accumulator 838. A diverter valve under control of a microprocessor 850 having sensors 852, 854 to sense the temperature of the batteries and the air in the passenger compartment determines the proper amount of refrigerant to allocate between the evaporator 834 serving the batteries and the evaporator 894 serving the passenger compartment air, based on the temperatures and the requirements of each system.
The batteries in each set may be air cooled via spaces between the batteries in between which air can blow through. Air cooling may be used in addition to the liquid cooling described above, or in place of it. In one embodiment, inserts to be added to the substrates are used to mount the batteries using integrated cooling holes and mounts as are described more completely below. The substrate is made of a glass-fiber-containing material for strength and rigidity, yet the insert is made of a more flexible material for better battery holding properties. Both the substrate and the inserts contain air holes into which air may be blown, or out of which air may be removed through suction, or both. The air holes may be integrated with the mounts, so that the air can blow directly into the spaces between the batteries, and yet the mounts do not interfere with the air cooling.
Referring now to FIGS. 10A-10D, a portion of an insert 1016 including integrated mounts 1018 with integrated air cooling holes 1012 in each of the mounts 1018, is shown according to one embodiment of the present invention. In one embodiment, insert 1016 is placed between the substrate and one or more batteries, although in another embodiment, the features of insert 1016 are part of the substrate. In one embodiment, insert is made of any flexible, insulating material and may be different from, or the same material as, the substrate.
FIG. 10A is a top view of a portion of a portion of an insert 1016 with batteries, such as battery 1008 inserted into the mounts 1018. In one embodiment, some mounts are shared between two or three batteries, such as the mount shown in the center of FIG. 10A. In one embodiment, each mount 1018 has the shape of a short hollow tube that is molded above a hole running through the insert 1016, with the hollow portion running perpendicular to the substrate 1016.
A flat cross piece 1010 may be molded between pairs of mounts 1018 just outside the space for the battery 1008 to add strength to the mounts. In one embodiment, cross piece 1010 does not extend the entire distance between nearby mounts, but instead runs a very short distance (about ¼ of that shown), with only one cross piece per mount instead of the three shown. When air cooling is to be used, each of the mounts is over a hole in the substrate to allow air from one side of the substrate through the hole in the insert, and through the mount 1018 to cool the batteries. Air may be removed from in between the batteries or exhausted through the opposite substrate as described below.
FIG. 10B shows a step in the process of building the mounts 1018, which are injection molded to the insert 1016. Referring now to FIG. 10B, bit 1020 is drilled into the insert 1016 just under the point where the injection-molded mount 1018 will contact the battery, although in one embodiment, the shape that would result from such drilling, or another shape that serves the same purposes, is in fact molded into the mounts 1018, and no drilling occurs. FIG. 10C shows the holes from the underside of the insert 1016 when the main hole for the mount 1018 has three holes, including hole 1014 (also shown from the opposite side in FIG. 10A) drilled at its edge. The holes such as hole 1014 in FIG. 10C drilled by bit 1020 of FIG. 10B allow the mount 1018 to deform when the battery is inserted between the mounts, to prevent the deformity of the mount 1018 that would otherwise occur from deforming the insert and the substrate so as to allow them to maintain their substantially flat shape, and help the mounts 1018 hold battery 1008.
FIG. 10D is a side view of battery 1008 inserted into the mounts 1018. Cross piece 1010 is also shown. In one embodiment each battery connection hole 1022 is more clearly shown in FIG. 10D. In one embodiment, there is one key 1022 under each battery, though other embodiments may employ fewer or more keys. Each key is a single, hollow tube extending downward from insert 1016. The hole in the substrate is similar to hole 230 of FIG. 2, but no mount exists in the substrate. Each key 1022 fits into a different hole in the substrate. Each hole in the substrate is nearly the same diameter as the outer diameter of key 1022, with the key extending from the bottom of the insert 1016 with a length substantially as long as the substrate is thick. Into the portion of the insert 1016 above key 1022 is a hole, either molded or drilled therein to allow connection to the battery terminals as described above in a manner similar to hole 344 of FIG. 3. The key holds the insert 1016 in place against the substrate, and prevents the potting compound, or other heat conductive material described above, from flowing under the battery terminals, which could otherwise prevent a good electrical connection between the battery and the bracket.
As noted herein, the mounts 1018 are positioned above holes 1024 in the substrate and optionally, the conductors to allow air to flow through, if air cooling is to be used. The insert 1016 is mated to a hole 1026 in substrate 1006 and electrical connection is made with the brackets via hole 1026 and the hole in the key 1022. The hole in the key opposite the positive terminal of any battery 1008 has a diameter not larger than the positive terminal of the battery 1008 to ensure that the conductor below the substrate 1006 contacting the positive terminal of the battery does not short to the negative case of the battery 1008 if it is pushed towards it.
Referring now to FIG. 10E, two battery assemblies are shown with air handling equipment. In the assembly 1060 on the left, an 1050, 1058 or both draw air from duct 1052, flowing through cowell 1054 through a single assembly 1060 of batteries with air holes as described above and out duct 1056 in the direction indicated by the arrow. In another embodiment, shown with the assembly 1061 on the right, duct 1056 is not used, and fan 1059 draws air through the top of assembly 1061. In another embodiment, shown in FIG. 10F, air flows in the direction indicated by the arrow (or in the opposite direction) through multiple assemblies 1074 having air holes as described above via fan 1070 and cowell 1072. Any space between assemblies 1074 may be covered by ducting.
In one embodiment, the conductors are not adjacent to the substrate, and so a large number of smaller holes may be provided in the conductors to allow air to flow through the conductors generally, but the holes need not be positioned adjacent to a mount in the insert. In such embodiment, the density of holes may be greater around the periphery of the conductor than it is at the center, so as not to interfere with the current carrying capacity of the conductors at locations of high current.
Although the geometries described herein may be used in one embodiment, other embodiments may employ other geometries. For example, in a non-air cooled environment, the mounts need not be mounted over holes in the substrate.
Part of an example assembly according to the present invention is shown in FIG. 12A according to one embodiment of the present invention. FIG. 13 describes the method of assembly.
Referring now to FIGS. 12 and 13, a substrate 1210 is shown with multiple inserts 1216 mated thereto via keys in the inserts 1216 fitting holes in the substrate 1210, corresponding to step 1310. A tubing assembly 1214 is fashioned into shape, for example by bending 1312, and placed 1314 over the inserts 1216.
In step 1316, perimeter walls 1218 are mounted or bonded to the substrate 1210, and divider walls 1220 are inserted between the perimeter walls and may be mounted or bonded to the substrate 1210.
Batteries, not shown, are added 1318 to the mounts in the inserts as described above and potting compound or other thermally conductive material may be added to touch each of the batteries and the adjacent section of the tube, and then in step 1320, a mirror image set of inserts, not shown, are in step 1322, are mounted to a mirror image substrate, not shown, and mounted to the batteries via mounts and to walls 1216, 1218 as described above.
Brackets are connected to conductors 1324 and then connected to the batteries 1326 as described above, offsetting over two sets of batteries, each set having an opposite polarity, to connect the two sets in series, for example. An assembly showing an alternate design, including some of the batteries 1222 and the mirror image substrate 1224 is shown in an exploded view in FIG. 12B. Because FIGS. 12A and 12B are water cooled, the air holes in the substrate near the mounts are not employed.
If there are additional assemblies 1328, they are built as described in steps 1310-1326 and then connectors may be connected 1330 between the edge connectors of adjacent assemblies as described above.
The steps of FIG. 13 may be performed in different order than what is described, or may be interlaced with one another, mounting the batteries and the walls a few at a time, for example.
Referring now to FIG. 14, a method of mounting and electrically connecting batteries is shown according to one embodiment of the present invention. One or two or more substrates with mounts for each battery and holes for electrical connection to the batteries are provided 1410. In one embodiment, the mounts are molded into the substrate. In another embodiment, the mounts are milled into the substrate, as described above, and will now be described with reference to FIG. 15.
Referring momentarily to FIG. 15, a method of milling battery mounts into a substrate is shown according to one embodiment of the present invention. A first position is selected 1510 and a spinning bit is drilled 1512 part way into the substrate at the first position. A petal is milled 1514 by radiating the drill bit outward from the center of the first position, for example, along a line. The bit is brought back to the center of the first position, and another petal is milled 1516 outward from the center of the first position along any line different from (though potentially 180 degrees from) a line used to mill any other petal for that mount. If there are more petals to mill 1518, the method continues at step 1516 and if not 1518, if there are more positions on the substrate in which a mount is desirable or required 1520, the next position is selected 1526 and the method continues at step 1512 as described above, and otherwise 1520, holes may be drilled through the substrate into the center of some or all of the mounts 1522 to provide electrical access and the method terminates 1524. As noted, batteries may be inserted into the mounts as described below, and the holes drilled in step 1522 may be smaller than the diameter of the positive terminal of the battery to be inserted, so as to protect it from coming into contact with a conductor that may be pushed against it.
Referring again to FIG. 14, multiple batteries are inserted 1412 into the mounts at one substrate, such as the bottom or the top, with one battery per mount in one embodiment. The batteries are inserted as part of sets: the batteries in each set may be inserted with the same polarity of the battery inserted into the mount, but each set may be inserted with polarities inserted that are different from the one or two sets that will be electrically adjacent to it. Spacers may be inserted 1414 into mounts which may or may not be different from the mounts used for the batteries (e.g. the mounts used for the spacers may be narrower than the mounts used for the batteries). In the flowchart, step 1414 follows step 1412, but the two steps may be performed together, with some batteries being inserted and then one or more spacers, then more batteries and done or more additional spacers, etc. Other steps in the flowchart of FIG. 14 or 15 may be performed in this intertwined fashion with other steps or some steps may be performed in a different order than is shown.
One or more cooling tubes may be run 1416 among a path adjacent to some or all of the batteries and the same one or more cooling tubes or a different one or more cooling tubes may be run 1418 back in the opposite direction along the same path or an opposite path. Steps 1416 and 1418 may be combined by running a single cooling tube assembly near each battery. In this manner, each battery is adjacent to two flows, with one in either direction, although other numbers of one or more flows in any number of directions near each battery may also be used. A heat conductive material may be added 1420 to contact the tube or tubes and some or all of the batteries.
Another one or more substrates may be pressed 1422 on to the other end of the batteries that were inserted in step 1412 and the spacers inserted in step 1414 using a conventional press. The other one or more substrates are made with the mounts described above. The mounts may be differently sized depending on the polarity of the battery the mount will accept, or the same sized mount may be used for all polarities. The other one or more substrates of step 1422 may be mirror images of the one or more substrates of step 1414.
Multiple conductors with holes are provided 1430 as described above. Brackets may be inserted 1432 into the holes and each bracket may be electrically connected 1434 to a conductor, such as by wave soldering the brackets to the connector when most or all of the brackets are in the holes of the connector.
The brackets with the connectors and the batteries mounted in the substrates described above are brought together in steps 1436 and 1438, which may be performed essentially simultaneously, but will be described separately for ease and clarity of description. One or more brackets electrically attached to the conductors are electrically attached 1436 to one or two sets of batteries via the holes in the substrates. This may be performed by aligning the brackets protruding out of the holes in each of the one or more conductors, with the holes that expose the terminals of the batteries mounted in one or more substrates.
The alignment may cause each conductor to electrically connect one terminal of each battery in a set to the same polarity terminal of all of the other batteries in a set, and optionally to also connect to such terminals the terminals having the opposite polarity of all of the batteries in a different set. For example, if all of the batteries mounted in the substrate are to be divided into sets, and all of the sets are to be connected in series, there will be one conductor spanning one end of each two electrically adjacent pair of sets, with the ends of each set spanned by a single conductor having opposite polarities, and two additional conductors, each spanning one polarity of all of the batteries in one of the two “end” sets.
Thus, in one embodiment, all but one or two of the conductors are each aligned over the terminals of two complete sets of batteries, the batteries in each set being connected at the same polarity with the other batteries in the set by the brackets and conductors when placed in contact thereto. Two sets of batteries may be connected to the same conductor, with each of the two sets having opposite polarities being connected to the conductor. In one embodiment, the electrical attachment also includes a physical attachment, such as by spot welding, pressure contacting or low-temperature soldering each bracket to one terminal of one of the batteries. In one embodiment, each bracket has two or more connections (e.g. spot welds) to at least most of each of the battery terminals for redundancy.
A process similar to the process described above is repeated for the one or more substrates on the other side of the batteries 1438, with brackets attached to one or more conductors as described above with respect to steps 1430-1434 aligned to fit into the holes in the substrate of the opposite side of the substrate of step 1436 and the brackets are spot welded to, connected, or otherwise electrical brought into contact with, the terminals inserted into the mounts of that substrate. As noted herein, any conductors spanning two sets of batteries are offset from those of the other substrate so that zero or more conductors can each connect the different polarity terminals in each of two sets of batteries in series, and will, in part, connect the batteries within the set in parallel. It isn't necessary to weld the brackets to the batteries: any electrical connection between the bracket and battery terminal can be used.
The conductors at the ends of each series of sets of batteries may be coupled 1442 to one or more edge terminals and the one or more edge conductors of one pair of substrates that make up a battery assembly may be connected 1440, either physically, electrically or both, to an edge conduction of an adjacent pair of substrates that make up a battery assembly (each assembled as described above), so as to connect at least some of the batteries in each assembly in series or parallel. In one embodiment, step 1444 is performed via a single solid, but slightly flexible unit, which may be constructed without wires.
FIG. 16A is a side view of a portion of battery pack 100A according to one embodiment of the present invention. Referring now to FIG. 16A, batteries 110A and 112A are conventional rechargeable batteries such as Lithium-ion or Nickel metal hydride batteries. Substrate 118A and substrate 120A, in which the batteries are mounted, are described in the related application. Conductor 150A and conductor 140A are sheets of hole-punched copper layered over the substrates 118A, 120A, with holes in each conductor aligned over the ends of each battery. Substrates 118A and 120A serve to hold the batteries and prevent the batteries' positive and negative terminals from touching conductors 150A and 140A, respectively.
The batteries' positive terminals 114A are connected to conductor 150A by fusible links, such as wire bonds 144A, and the batteries' negative ends 116A are connected to conductor 140A by similar fusible links, such as wire bonds 142A via holes in the substrates 118A, 120A and conductors 140A, 150A. These wire bonds are one method of fusibly linking each battery to each conductor, and are described herein as a representative example; other methods of fusibly linking each battery to each conductor may be used in other embodiments. In one embodiment, each wire bond is a wire 15 mils thick, made substantially of Aluminum. The wire bond is made of an aluminum allow containing 50 parts per million of nickel for corrosion resistance and one-half of one percent of magnesium for added strength. The batteries are conventional.
The current carrying capacity of wire bonds 144A and 142A is slightly greater than the maximum expected current from one battery. In the event that the current carrying capacity is exceeded, the wire bond for that battery will break sufficiently to ensure that no arcing will occur, preventing the current from flowing between the battery 110A or 112A and the conductor 140A, 150A, and allowing the rest of the batteries in the pack to continue to function in the event of an overcurrent condition, such as a short circuit through the battery.
FIG. 16B is a top view of the battery pack 100A of FIG. 16A according to one embodiment of the present invention. Referring now to FIG. 16B, wire bonds 144A are connected in parallel to conductor 150A via holes 160A in the conductor 150A and underlying substrate (not shown). Conductor 150A may be cut to any shape to fit the arrangement of batteries in the available space.
FIG. 17 is a block schematic diagram of a set of two battery packs and a fuse according to one embodiment of the present invention. Referring now to FIG. 17, each battery pack 100AA, 100AB is constructed in the same or similar manner as battery pack 100A as described with reference to FIGS. 16A and 16B. Fuse 210A connects the conductor that is wire bonded to the positive ends of the batteries in battery pack 100AA to the conductor that is wire bonded to the negative ends of the batteries in battery pack 100AB.
The current carrying capacity of fuse 210A is just below the current carrying capacity of the sum of the wire bonds coupled to one conductor, or just above the maximum expected current through all the batteries in each pack 100AA, 100AB. In the event that the current carrying capacity of fuse 210A is exceeded, fuse 210A will blow, preventing the current from blowing out the wire bonds in the battery packs 100AA, 100AB, for example, in the event that a short occurs between terminals 220A and 222A.
Although fuse 210A is shown in this embodiment between the battery packs, in other embodiments it may be placed elsewhere, such as in front of, or behind, the series of battery packs 100AA, 100AB. Any number of battery packs 100AA, 100AB may be fusibly connected, in serial, in this manner. Terminals 220A and 222A end the chain of battery packs and the fuse 210A.
One or two or more of battery packs 100AA, 100AB with the fuse 210A may be added to a conventional hybrid or electric vehicle, such as an automobile or rocket to manufacture such a vehicle. Other products may be manufactured using one or more such battery packs, with or without fuse 210A.
FIG. 18 is a flowchart illustrating a method of fusibly coupling batteries according to one embodiment of the present invention. Referring now to FIG. 18, multiple batteries are mounted in substrates 310A. The positive ends of the batteries are mounted in one substrate and the negative ends of the batteries are mounted in a second substrate, as described above. The substrates are described in detail in a related application.
Each substrate is layered with a conductor 312A. Each conductor is placed on the side of the substrate that does not touch the batteries, so that the batteries and substrates are sandwiched between two conductors, as described above. As previously described, the conductors are sheets of copper that contain holes, and each hole is aligned over one end of one battery.
When the substrates have been sandwiched with conductors, the positive ends of each battery are fusibly linked to one conductor, and the negative ends of each battery are fusibly linked to the other conductor 314A. As previously described, in one embodiment, the fusible links are wire bonds that run through the holes in a substrate and conductor.
When each battery has been fusibly linked to each conductor, the battery pack is complete. As described above, two or more battery packs may be connected. In one embodiment, to connect two battery packs, the packs and a fuse are connected in series as described above 316A. Any number of battery packs and fuses may be serially connected in this manner. As used herein, a battery pack is a set of one, two, or more batteries in which some or all of the terminals of one polarity are connected to one conductor and some or all of the terminals of the other polarity are connected to another conductor.
FIG. 19 is a block schematic diagram of a system of interconnected battery packs according to one embodiment of the present invention. FIG. 19 shows parallel interconnected battery packs, but battery packs may be connected in series as is shown in FIG. 21, and battery packs may be connected in series and parallel as is shown in FIG. 25.
Referring now to FIG. 19, battery pack 112B is electrically coupled via flexible bus bars 130B, 150B to battery pack 114B. Battery pack 114B is similarly coupled electrically to battery pack 116B. In one embodiment, each pack 112B, 114B, 116B is adjacent or nearly adjacent to each of the other packs 112B, 114B, 116B. In one embodiment, each battery pack 112B, 114B, 116B consists of a set of battery bricks connected in series as described below. Each battery brick is a set of batteries connected in parallel to one another, as described below. The battery bricks are not separately shown in the Figure, but are shown in the related application as sets of parallel-connected batteries.
Battery pack 112B is selected as a representative pack, but packs 114B and 116B are constructed in the same manner. Each terminal 130B, 140B of battery pack 112B is a metal connector on the outside edge of battery pack 112B. Each terminal 130B, 140B is connected to one of the terminals of the brick at the edge of the set of bricks. Each terminal 130B, 140B extends from a side of the pack 112B, such as the top or bottom, and then folds over to a plane parallel to another side of the pack. The first side may be open so that the batteries are exposed to view, access or both, and the other side may be sealed so that the batteries are not exposed to view or access. The open side permits the terminal 130B, 140B to extend from the pack 112B without interference and the second side prevents screws intended for the terminal 130B, 140B from falling into the pack 112B.
A flexible bus bar 150B connects external terminal 140B of battery pack 112B to an external terminal of battery pack 114B. In one embodiment, flexible bus bar 150B is a conventional mesh-like, flexible ribbon or tube of multiple, thin wire strands which allows a very high current carrying capacity while reducing the danger of stresses and fractures to the assembly. In one embodiment, flexible bus bar 150B is a conventional flexible bus bar, such as may be fabricated using conventional ground braids, such as the conventional FTCB 15-35 ground braid with a crimped-on lug commercially available from Erico, of Solon, Ohio (at the website of Erico.com). The extreme flexibility of flexible bus bar 150B relative to ordinary electric facilities that can carry a similar current as that which can be carried by the flexible bus bar 150B is advantageous in a high vibration environment, such as the engine of a car, because the wiring will not break or fracture itself, or the components to which it is connected, as those components vibrate or move relative to one another. A non-flexible method of wiring, particularly a non-flexible method of wiring that is expected to carry a high level of current like a solid conductor, could fracture or break, or induce fractures or breaks in the packs 112B, 114B, 116B.
Battery pack 114B and battery pack 116B are coupled to one another in a similar manner, and any number of additional battery packs may be coupled to one another in this manner. FIG. 19 illustrates battery packs coupled in parallel; however, as shown in more detail in FIG. 21, battery packs may also be coupled in series using the flexible bus bar arrangement described herein. Other arrangements could couple some battery packs in series and others in parallel, according to the voltage and current needs of the device or devices that use the current and voltage supplied by the battery packs 112B, 114B, 116B.
Referring now to FIG. 21, a set 300B of interconnected battery packs 312B, 314B, 316B is shown according to another embodiment of the present invention, and a flexible bus bar 390B is shown in more detail. Battery packs 312B, 314B, 316B are similar to battery packs 112B-116B shown in FIG. 19. As described in the related application Ser. No. 11/129,118, the series connections of each brick in a battery pack such as battery pack 316B is made via a solid conductor spanning two bricks. Each brick has a set of batteries oriented in the same polarity, but opposite to that of the electrically adjacent brick. Thus, the batteries in each brick are oriented upside down relative to the batteries in the adjacent bricks. A single solid conductor not only connects one of the polarity terminals one set of batteries in one brick to one another in parallel, but many of them extend to also connect the opposite polarity terminals of another set of batteries in an adjacent brick to one another in parallel. The effect of using this single conductor is to connect the two sets of batteries in series to one another. For example, a conductor can be in electrical contact with the positive terminals of the batteries in brick 1, as well as the negative terminals of the batteries in brick 2, connecting brick 2 in series with brick 1. There may be any number of series-connected bricks in a battery pack, though, as mentioned above, in one embodiment, the number of bricks is nine. Each brick in a given battery pack is therefore adjacent to any other brick to which it is directly connected in series in this manner.
The conductors at either end of the series of bricks contact just the conductors of one brick. So, using the example above, if brick 1 is the end of the series of bricks, the negative terminals of the batteries of brick 1 may be electrically connected via a conductor, which is coupled to the edge terminal of the battery pack. For example, conductor 324B, shown in the Figure, may be the negative terminal for the battery pack. (The remaining conductors are not shown to avoid cluttering FIG. 21, but are shown in more detail in FIGS. 22A and 22B.) In one embodiment, the conductor 324B is electrically connected to, or forms, a terminal 320B, which is used as the negative terminal for the battery pack 316B. In one embodiment, terminal 320B is actually a part of conductor 324B, formed by bending a tab extending from conductor 324B at a 90 degree angle, although other embodiments may have an electrical connection such as a weld. Each of the battery packs 312B-314B may use a similar construction as that described above for battery pack 316B.
In one embodiment, the flow of current through the battery bricks, looking at the narrow side, would be seen as back and forth through adjacent sets of parallel-connected battery bricks. However, when viewed from the flat face of the pack 312B-316B, the flow of current is circular, starting at one terminal, such as terminal 322B and ending up at approximately the same position (though on the opposite face as the current started). This enables the two terminals on the battery pack to be located at the same height as one another, allowing for short series connections between adjacent battery packs 312B-316B. This is achieved via placement and shape of the conductors within each pack, as will now be described.
Referring now to FIGS. 22A and 22B, an arrangement of the conductors on either side of a battery pack are shown according to one embodiment of the present invention. Conductors 410B, 414B, 418B, 424B and 428B are on the far side of substrate 400B and conductors 412B, 416B, 420B, 422B, 426B and 430B are on the near side of substrate 402B. When substrate 402B is placed behind substrate 400B and sets of batteries are placed between them, the conductors and batteries form an electrical connection from edge 450B to edge 452B or vice versa. For example, the positive terminals of a set of batteries are electrically connected to conductor 410B, such as may be described in the related application. The positive polarity terminals of that same set of batteries are electrically coupled to the lower half of conductor 412B. Negative terminals of another set of batteries are electrically coupled to the upper half of conductor 412B, and the positive terminals of that other set of batteries are electrically coupled to the right half of conductor 414B. Thus, the two sets of batteries are coupled in series to one another. Multiple sets of batteries are coupled in this manner via the conductors 410B-430B, with current flowing in numerical order of the conductors, or in reverse order, with the resulting flow being circular when viewed from the flat face of the pack. However, conductors 420B and 422B operate as a single conductor, with fuse 440B electrically coupled between them to electrically protect the batteries as described in the related application. In one embodiment, a bus bar similar or identical to that described herein is used in place of fuse 440B in the event that fusing is not desired or required.
End 450B of edge conductor 410B and end 452B of edge conductor 410B is folded 90 degrees to form a terminal, in a manner similar to that shown for terminal 320B of edge conductor 324B of FIG. 21. Referring again to FIG. 21, the terminal of one pack 312B, 314B, 316B is electrically connected to the nearest terminal of another pack 312B, 314B, 316B using a flexible bus bar 390B, for example, as shown between packs 314B-316B. No flexible bus bar is shown between packs 312B and 314B, but one could be installed there if a series connection between the two packs 312B, 314B was desired. Any number of packs may be connected using any manner described herein.
In one embodiment, the flexible bus bar 390B is made of a conventional braided conductive metal 350B, such as copper or aluminum, onto which conductive terminals 360B, 370B may be crimped or otherwise electrically connected. Each terminal may have a hole, such as hole 380B, to accept a screw, which is inserted through hole 380B, and threaded into a hole 322B in terminal 320B of any battery pack. The hole 322B may be threaded or self tapping screws may be used. When the screw, thus inserted and threaded, is tightened, it physically and electrically connects the terminal 320B to the bus bar 390B. The head 340B from such a screw is shown in the FIG. with the screw head 340B parallel to the face of the pack 312B, the terminal of which the screw is threaded into.
A similar connection is made to the opposite polarity terminal of the adjacent battery pack using the other terminal of the same bus bar.
In one embodiment of the present invention, the terminal conductors are shaped to allow series connections, parallel connections or both. Referring now to FIGS. 22C and 22D, the conductors are the same as described above with reference to FIGS. 22A and 22B, respectively, but the terminal conductors 410B and 430B of FIGS. 22A and 22B have been replaced with conductors 411B and 431B of FIGS. 22C and 22D. Conductor 411B has terminal 451B that is folded over the face of the battery pack (or is coupled to a terminal on that face) and conductor 431B has terminal 453B that is folded over the face of the battery pack or is coupled to a terminal on that face. In all other respects, the position of the conductors and flow of current is the same.
Referring now to FIG. 25, a battery assembly 500B containing four battery packs 512B-518B is shown. Each battery pack 512B-518B is similar to that of battery packs 312B-316B, except that they use the conductors shown in FIGS. 22C and 22D to connect the batteries in each set to one another in parallel and to connect adjacent sets of batteries to one another in series. This is in contrast to the battery packs of FIG. 21, which employ the conductors of FIGS. 22A and 22B. Packs 512B and 514B are coupled to one another in series via flexible bus bar 522B and packs 516B and 518B are coupled to each other in series via flexible bus bar 524B. Each pair of series-coupled packs 512B, 514B being one pair and 516B, 518B being another, are coupled in parallel via flexible bus bars 530B, 532B.
Each of the terminals used for the series connections are at or near the same height relative to the bottom edge of the battery packs 512B-518B. Each of the terminals used for the parallel connections of one polarity are at the same height relative to the bottom edge of the battery packs 512B-518B. The terminals used for the series connections are at a height relative to the bottom edge of the battery packs 512B-518B that is different from the height, relative to the bottom edge of the battery packs, of each terminal used for the parallel connections, and each polarity of the terminals used for the parallel connections are at a different height, relative to the bottom edge of the battery packs 512B-518B from one another. This arrangement ensures that the flexible bus bars remain as short as possible and do not cross one another.
Insulators (not shown) may be placed over the terminals that flexible bus bars 530B and 532B cross, to avoid a connection between the bus bars and those terminals. In another embodiment, flexible bus bars are insulated. In still another embodiment, the unused terminals are scored just behind the bend, to allow them to be snapped off and removed, so that connection to the bus bar is not possible.
This manner of extending terminals from the battery packs allows for complete flexibility of connection. The two edge terminals 540B, 542B may be used as terminals for the assembly.
FIG. 20 is a flowchart illustrating a method of connecting battery packs according to one embodiment of the present invention.
Referring now to FIG. 20, a set or sets of batteries are connected in parallel 210B to form battery bricks. To connect the set(s) of batteries in parallel, the method described above, and in the related applications, may be used.
In one embodiment, as described above, battery bricks (e.g. nine battery bricks) are coupled in series to form battery packs 212B. In one embodiment, step 212B includes connecting the battery bricks in such a manner that the terminals will appear at opposite sides of the battery packs as described above. In one such embodiment, current flows back and forth between the opposite sides of the battery pack, and relative to the sides of the pack, flows in a circle around the periphery of the pack as described above. At each end of the series connection, two terminals will exist, one of each polarity.
Packs are stacked adjacent, or nearly adjacent, to one another 214B that will not be between the stacked packs. Battery terminals are extended to the edge of each battery pack 216B. To extend the terminals to the edge of the pack, conductive materials, such as metal plates, are positioned on an outside edge of the battery pack and connected to, or formed into, each of two terminals at the end of the series connection described above to extend the flow of current to the exterior of the battery pack. In one embodiment, the two terminals extend from the top and bottom of the pack, and in another embodiment, the two terminals extend from either side of the pack, and in still another embodiment, there are four terminals as described above: one for series connection and another for parallel connection and each of the terminals for a pack fold over the same side of the pack, to save space and eliminate the possibility that screws will fall into the pack, as described above.
A terminal from one battery pack is connected to one a terminal from at least one other battery pack using a flexible bus bar 218B. To connect the external terminals with a flexible bus bar, each end of the flexible flex bar is physically and electrically connected to the terminals on adjacent battery packs. For example, a screw may be inserted through a terminal connector of the flexible bus bar to a threaded hole on a terminal of the battery pack to connect each end of the flexible bus bar to a terminal of a different battery pack. The multiple, thin wire strands of the flexible bus bar allow a high current carrying capacity with a minimal danger of stresses and fractures in the flexible bus bar or battery pack in a high vibration environment, as described above. In one embodiment, the battery packs may be coupled in parallel as illustrated in FIG. 19, or in another embodiment, the battery packs may be coupled in series as illustrated in FIG. 21, in each case via one or more flexible bus bars. In another embodiment, a combination of series and parallel couplings are used. In one embodiment, the current carried by the flexible bus bar is in excess of 30, 50, 100, 150, 200, 250, 300 or 500 amps.
The batteries thus connected may be coupled to the power source of an electric or hybrid vehicle, such as an electric motor of an automobile or rocket 220B.
The method of FIG. 20 may be use to build the battery assembly consisting of two or more battery packs and one or more interconnecting bus bars, and such a battery assembly may be used to build an other products. Such products may include some or all of the power storage and supply of a battery- or hybrid-powered automobiles, rockets or other vehicles 610B of FIG. 24. The steps of FIG. 20 are used to construct the battery assembly, such as those described with respect to FIG. 19, 21 or 23, either in the vehicle, or separately so that it may be added to the vehicle. The remainder of the vehicle may be constructed using conventional techniques.
Referring now to FIG. 25A, a system of battery cells inhibited from thermal chain reactions is shown according to one embodiment of the present invention. The system of more than one battery cell is referred to as an “battery cell pack” or “battery cell assembly”, which mean the same thing as used herein and is one form of an “electrical storage pack”. In one embodiment, the battery cells 108C have a substantially cylindrical shape, though any form factor used for storing energy may be used, such as prismatic cells. The battery cells 108C may be any type of energy storage device, including high energy density, high power density, such as nickel-metal-hydride or nickel-cadmium, nickel-zinc, air-electrode, silver-zinc, or lithium-ion energy battery cells. Battery cells may be of any size, including mostly cylindrical 18×65 mm (18650), 26×65 mm (26650), 26×70 mm (26700), prismatic sizes of 34×50×10 mm, 34×50×5.2 mm or any other size/form factor. Capacitors may also be used, such as supercaps, ultracaps, and capacitor banks may be used in addition to, or in place of, the battery cells. As used herein, an “electrical storage pack” includes any set of two or more devices that are physically attached to one another, capable of accepting and storing a charge, including a battery cell or a capacitor, that can fail and release heat in sufficient quantity to cause one or more other nearby devices capable of accepting and storing a charge, to fail. Such devices are referred to herein as “power storage devices”.
The battery cells 108C, such as battery cell 110C, in the assembly 100C are mounted in one or more substrates, such as substrate 112C, as described in the related application. There may be any number of battery cells 108C in the assembly 100C. Although only three battery cells 108C are referenced in the Figure to avoid cluttering it, all of the circles are intended to be referenced by 108C. The battery cells 108C are located nearby one another, for example not more than 20 mm center-to-center distance for battery cells 108C that have a maximum diameter of 18 mm. Other embodiments have spacing under one quarter or one half of the center to center distance, making the spacing between the battery cells less than half the width of the battery cell in the plane that spans the center of each pair of battery cells. In one embodiment, the center-to-center distance for the battery cells 108C (measured from the center of a battery cell to the center of its nearest neighbor) does not exceed twice the maximum diameter of the battery cells, although other multiples may be used and the multiples need not be whole numbers. Not all of the battery cells 108C in the system need be spaced as closely, but it can be helpful to space the battery cells relatively closely, while providing adequate space to ensure the thermally-conductive material, described below, has room to be added.
In one embodiment, the substrate 112C is that described in the related application. Briefly, the substrate 112C is a substrate sheet containing holes that are surrounded by mounting structures that hold the battery cells firmly against the substrate, positioned with the terminals of the battery cells 108C over the holes, with each of the battery cells 108C located between two of the substrates. Different substrates such as substrate 112C are located at either end of each of the battery cells and the different substrates in which each battery cell is mounted are located approximately one battery cell length apart from one another (only one substrate is shown in the Figure, but another one would be pressed onto the tops of battery cells 108C. The radius of the holes is equal to or lower than the radius of the battery cells 108C at the hole.
The battery cell mounting process involves inserting the battery cells 108C into one or more substrates 112C at one side, such as the bottom. Cooling tubes 114C are added adjacent to each of the battery cells 108C as described in the related application and carry a coolant to absorb and conduct heat, though it is noted that the coolant in the cooling tubes 114C may not be a significant thermal conductor relative to the potting compound described below.
A thermally-conductive material such as thermally-conductive potting compound or another thermally-conductive material 116C is poured or placed around the battery cells 108C so that the battery cells having 65 mm height are standing in the potting compound or other thermally-conductive material 116C at least to a depth of approximately 6 mm that will cover a part of the battery cells and the cooling tubes. Other embodiments may employ other depths, which may be approximately 5%, 15%, 20%, 25%, or 30% of the height of the battery cell.
In one embodiment, the conventional Stycast 2850kt, commercially available from Emmerson and Cuming Chemical Company of Billerica, Mass. (Web site: emmersoncuming.com) is used as the potting compound 116, though any potting compound or other material with a high thermal conductivity can be used. The Stycast catalyst CAT23LV is used with the potting compound.
It is not necessary that the thermally conductive material quickly release heat to the nearby battery cells or the ambient air. In one embodiment, the thermally conductive material absorbs more than a nominal amount of heat. For example, in one embodiment, the thermally conductive material is selected so that at least some of the thermally-conductive material nearby a battery cell that is experiencing a failure will undergo a phase change, for example, from a solid to a liquid or from a liquid to a gas. For example, the thermally-conductive material may contain a material that will undergo such a phase change and that is micro-encapsulated in the thermally conductive material, allowing the thermally-conductive material to more rapidly absorb additional heat. The heat may therefore be dispersed to the nearby battery cells and the ambient air over time, causing the adjacent battery cells to absorb less heat and to do so more gradually.
The thermal conductivity of the thermally conductive material 116C poured or placed around the battery cells 108C should be high enough to absorb the heat generated from any battery cell (for example, battery cell 110C) that is venting gases in a worst case scenario and absorb it or distribute it to the air and to many of the battery cells 108C, including those nearest to the battery cell 110C generating the heat as well as others farther away from the nearest battery cells, without allowing any of the battery cells to which heat is being distributed to reach a temperature that would cause a self sustaining reaction that would cause any such battery cell to fail or vent gases. The thermally-conductive material may also distribute heat to the nearby cooling tubes and coolant contained therein.
In one embodiment, the potting compound or other thermally-conductive material 116C is poured into the spaces between the battery cells 108C in liquid form, which hardens to a solid or semi-solid material. Although solid materials such as hardening potting compounds can prevent leakage, potting compounds that remain somewhat liquid may be used. The potting compound or other thermally-conductive material 116C contacts the case of each battery cell as well as any nearby battery cells so that heat released from one battery cell due to physical (e.g. crushing), chemical or other causes will be rapidly transferred to many nearby battery cells as well as the potting compound itself and the substrate with which it is in contact. The potting compound or other thermally-conductive material 116C may have electrically insulating qualities or may be conductive. However, in one embodiment, the potting compound is not used solely to conduct electricity, connections on the battery cells being separately provided instead, for example, using the method described in the related application.
A second one or more substrates are added to the top of the battery cell assembly, and conductors are sandwiched around the substrates as described in the related application.
FIG. 25B is a side view of two rows of the battery cells after the potting compound has hardened among the battery cells and the tubes. The potting compound 116C will conduct any heat from one battery cell 110C that is overheating to many more of the battery cells than would have occurred if no potting compound was used. Not only is the heat spread to the immediately adjacent battery cells 120C, it is also spread to more distant battery cells 130C, as well as being absorbed by the potting compound 116C itself and optionally substrate 112C before dissipating into the ambient air (as noted, the upper one or more substrates are not shown in the Figure). This effect distributes the heat from the battery cell 110C experiencing the failure, among multiple battery cells 120C, 130C and the potting compound or other thermally conductive material 116C, reducing the heat that will be absorbed by any one battery cell, and thereby reducing the chance that a second battery cell will achieve a temperature sufficient to cause a thermal reaction (which would cause the second battery cell to fail), optionally to the point of venting gases, resulting from the release of heat of the first battery cell.
FIGS. 25C and 25D are side and top views illustrating battery cells in a thermally conductive material according to another embodiment of the present invention. Referring now to FIGS. 25C and 25D, in this embodiment, the thermally conductive material 150C is a solid, such as a sheet of aluminum or other thermally conductive material. Holes 154C in the sheet 152C are inserted over the battery cells 152C or the battery cells 152C are inserted into holes 154C in the sheet 150C. A bushing 156C or another thermally-conductive material that can thermally couple the battery cells 152C to the sheet is inserted among them to thermally couple each of the battery cells 152C to the sheet 150C. In the case that the sheet is electrically conductive, the bushing 156C can be made of thermally conductive, but electrically insulating material. In one embodiment, potting compound may be used as the bushing 156C. The cooling tubes may be thermally coupled to the sheet 150C.
Referring now to FIG. 26, a method of manufacturing a chain-reaction-inhibiting battery cell pack and distributing heat generated from one battery cell to more than one other battery cell is shown according to one embodiment of the present invention. Multiple battery cells are mounted 210C in a substrate. One or more tubes containing a coolant such as water, are run 212C adjacent to each battery cell. In one embodiment, the coolant in the tubes runs in both directions past the battery cells, so that the coolant flows between the battery cells, turns around, and then flows out from between the battery cells in a counter-flow manner as described in the related application. Thermally conductive material such as potting compound is placed 214C in between the battery cells and may contact the tubes and optionally fully or partially hardens or becomes harder among the battery cells and the tubes, contacting the battery cells and the tubes. In the event of a reaction in which heat is generated from one of the battery cells and excess heat is released, for example, via a venting of heat and gases from one or more battery cells 216C, such as could be caused by an internal short or a random thermal reaction starting in one or more of the battery cells, the thermally conductive potting compound will draw 218C the heat released from the battery cell to a wide area, wider than would have been likely if no potting compound was used, and will distribute 220C the heat to several of the battery cells, spreading the heat among more battery cells than would have occurred without the potting compound, and reducing the chance that the temperature of any of the adjacent battery cells immediately after the original release of heat will rise sufficiently to cause any such other battery cell to thermally react to the point of full or partial failure, such as by venting heat and gases. Step 218C may include a phase change of at least some of the material in the potting compound as described above.
Referring now to FIG. 27, a conventional vehicle 410C such as an electric-, hybrid-, or plug-in hybrid-powered car is shown according to one embodiment of the present invention. The battery cell assembly 320C produced as described above may be added to a conventional fully-, or partially-electric powered vehicle 310C, such as an electric, hybrid or plug-in hybrid car or rocket. The battery cell assembly may be coupled to, and supply power to, an electric motor (not shown) powering the vehicle.
One or more battery cell assemblies according to the present invention may be used to build a conventional uninterruptible power supply, or other battery back-up device, such as that which may be used for data center power, cell-tower power, wind power back up or other backup power. One or more battery cell assemblies may be used to build hybrid power vehicles or equipment, electrical peak shaving equipment, voltage stability and/or regulation equipment or other equipment.
FIG. 28 is a flowchart illustrating a method of assembling an electric motor according to one embodiment of the present invention. FIG. 29A is a diagram of an exploded view of a rotor according to one embodiment of the present invention. FIG. 29B is a diagram of a portion of the rotor of FIG. 29A according to another embodiment of the present invention. The method of FIG. 28 is described alongside the diagrams of FIGS. 29A and 29B, however, the rotor and method may be practiced independently of one another: e.g. the method of FIG. 28 may be used on a rotor different from that shown in FIG. 29A or 29B and vice versa.
Referring now to FIGS. 28, 29A and 29B, laminated steel discs 210D are stacked 110D. A representative disc 210D is shown in more detail in FIG. 30. Referring now to FIGS. 28, 2A, 2B, and 3, in one embodiment, each of the discs 210D is substantially round in shape, and each of the discs has teeth 310D radiating outwards from a central portion. In one embodiment, the teeth 310D have a portion 314D forming a trapezoid that is nearly rectangular in shape, the longest sides being approximately one-half to five degrees out of parallel (e.g. 0.75 degrees), the teeth being slightly wider at the outermost edge than the width at the innermost edge of the trapezoidal portion 314D. In between each of the teeth 310D are spaces 312D that form a substantially triangular shape. The discs 210D are stacked to allow the teeth 310D from adjacent discs to be aligned with one another so that the stack forms spaces 312D between each pair of adjacent teeth 310D, the space 312D forming two sides of a triangle. In one embodiment, a part of each disc 210D is keyed to allow imperfections in the shape of the discs 210D to be matched by any disc above or below it. The triangular shape of the spaces 312D between the teeth 310D take up the larger circumference of the outer portion of the discs relative to their inner portions.
Bars 212D having a substantially triangular cross section (or another shape that fits in the spaces 312D between the teeth 310D) are inserted 112D into the spaces between the teeth 310D of the discs 210D. In one embodiment, the bars may be tapped into the stack of discs 210D using a rubber mallet. In one embodiment, the teeth 310D have T-shaped ends to hold the bars 212D in place. The bars may be made of copper or made of another material, for example, copper with silver plated ends. Each of the bars 212D is longer than the stack of discs 210D, so that each of the bars 212D stick out from either end of the stack of discs 210D. Between the outer ends of the bars 212D, a space is formed, allowing slugs 214D, described below, to be radially inserted in the spaces between the bars 212D and above and below the teeth 310D of the discs 210D in the manner described below. The spaces between adjacent bars 212D at each of their ends have a nearly square shape, with the faces of adjacent bars 212D being only a small amount out of parallel as described above, and the spaces are wider at the opening of such spaces from the outer portion of the rotor assembly 200D than the width of the spaces nearer to center of the rotor assembly 200D.
Slugs 214D having a substantially rectangular cross section or another cross section at least similar to portion 314D of teeth 310D, are radially inserted 114D in the spaces between the bars above and below the teeth. As shown in FIG. 31, the slugs 214D have not yet been inserted. The slugs are inserted from their positions shown in FIG. 31 to their positions shown in FIG. 29 by pushing and optionally tapping them with a rubber mallet towards the axis of the rotor assembly 200D. In one embodiment, a disc (not shown) with beveled edges that has a diameter slightly larger than the diameter of the circle defined by the inner edges of the bars 212D nearest the bolt 220D is placed over the bars 212D (and may have a hole to accept bolt 220D to properly center the disc and maintain its position) so that the beveled edge of the disc touches the inner edges of the bars 212D. The slugs 214D are slightly longer than the portion of the bars 212D that extends past the stack of discs 210D so that if the slugs 214D are inserted between the bars 212D directly above or below the stack of discs 210D, the slugs 214D will extend further from the discs than the ends of the bars 212D. Because of this extra length, the disc with the beveled edge will serve as a stop as the slugs 214D are being tapped in towards bolt 220D to ensure that the slugs 214D are inserted uniformly, almost to the inner edge of the bars 212D. The disc may be removed and another disc having a greater diameter may be placed over the top of the slugs 214D and the disc is tapped in the direction of the discs 210D to seat the slugs towards, or against, the discs 210D. The same procedure may be used to insert and seat the slugs 214D on the opposite end of the rotor assembly 200D. The discs 210D at each end may be used in a conventional press to press the discs towards one another, further seating the slugs 214D against the stack of discs 210D.
In one embodiment, the slugs 214D, like the bars 212D, are made primarily of copper. A plating or coating of a braising material is made to either the slugs 214D, the ends of bars 212D, or both. In one embodiment, the braising material is pure silver. The plating or coating will cause the bars 212D and slugs 214D to braise to one another when the two are sufficiently heated. In one embodiment, the bars 212D are made of copper and the slugs 214D are made of copper, plated with pure silver. One advantage of this method and rotor is that the slugs 214D and the bars 212D can be extremely tight-fitting: because the slugs can be inserted fewer than all at the same time (e.g. one at a time), the full force of insertion can be devoted to the fewer than all slugs being inserted, whereas a cap piece with fins requires all of the fins to be inserted simultaneously. Because all of the fins are inserted simultaneously, the force of insertion delivered to each one is less than all of the force, and the tolerances are made larger to accommodate the lack of available force of insertion.
In contrast to conventional rotors using cap pieces, the slugs 214D are not mechanically or electrically attached to one another before they are pushed into the spaces between the bars. The slugs 214D may, however, be mechanically or electrically attached, however, doing so would have little functional value. Thus, mechanical or electrical attachment of the slugs 214D to one another via some mechanism other than a conventional cap plate and that would enable the slugs 214D to be pushed axially into the rotor assembly 200D is permitted, but not required.
An optionally thermally-expandable force is applied 116D to the ends of the slugs 214D towards the center of the rotor assembly 200D to press the ends of the slugs 214D against the outer faces of the nearest disc 210D at each end of the stack. To apply such a force, in one embodiment, a green chromate coated stainless steel plate 222D is slipped over bolt 220D running along the axis of the stack of discs 210D and extending beyond the tips of the slugs 214D and bars 212D. The green chromate coating may be replaced with any coating that will help prevent the piece coated from brazing to the slugs 214D, bars 212D or any other portion of the rotor assembly 200D and need not actually be a green color. A nut 224D is tightened over the plate 222D using the bolt 220D. The plate 222D is used to distribute the force across the edges of the slugs 214D and bars 212D. A spring (not shown) is optionally placed between the plate 222D and the nut 220D at each end to allow for thermal expansion of rotor assembly 200D, though other means of doing so, such as by using a bolt 220D with an approximately equal or slightly lower coefficient of thermal expansion than the remaining portion of rotor assembly 200D may be used. This same arrangement is used on the other end of the rotor assembly 200D. The force is thus axially applied from the ends of the rotor assembly 200D towards its center.
An optionally thermally-expandable force is applied 118D radially, from outside the slugs 214D towards bolt 220D. The force may be applied in such a manner that it is present before and during the heating of the slugs 214D or it may be applied in a manner that causes it to be present when the slugs are heated, but not before, or the force may be very light before the slugs are heated but may increase as the slugs are heated if the application of the force is via one or more components that have a lower coefficient of thermal expansion than the remainder of assembly 200D. The force is applied in a manner that allows for it to be removed at a later time.
In one embodiment, the force is applied by the use of a removable collet 232D made of green-coated stainless steel, and a collar 230D at either end of the rotor assembly 200D. The collet 232D, with the collar 230D slipped over it, is slipped over the slugs 214D and the ends of the bars, and screws are inserted into holes 240D and tightened with bolts. The collar 230D is tightened together with the collet 323D, using one or more bolts and nuts through holes such as hole 236D and hole 238D. The collar 230D and collet 232D are shaped in such a manner that causes them, when tightened in this manner, to compress the slugs 214D towards bolt 220D. The collet 232D and collar 230D distribute the force of the tightening inward towards bolt 220D without adding torque to pull the slugs 214D or bars 212D out of position. Alternative solutions such as clamps could distribute the force inwards towards bolt 220D but could torque the slugs 214D or bars 212D in a circular fashion, which could provide a less-tight connection between one of the faces of slugs 214D and bars 212D. The compression used has the effect of forcing both faces of the slugs 214D against the faces of the bars 212D to tighten them during the brazing process described below, for a higher conductivity between their faces.
In one embodiment, the collet 232D contains fins such as fin 234D that have a wedge shape. That is, the part of the fins 234D contacting the collar 230D get thicker between the face that faces the slugs 214D and the opposite face at the base of the fins 234D as the screws tightening the collar 230D are tightened. The effect is to provide a “radially wedging” effect that provides the radial force. A radially wedging effect is the application of a radial force caused by a wedge shaped piece sliding over another piece or being slid over by another piece. This radial force is centrally-directed, that is directed inward towards the axis of bolt 220D.
In one embodiment, the bolts used to tighten the collar 230D and collet 232D are tightened against a spring to allow the collar 230D to expand slightly in response to the thermal expansion of the bars 212D and slugs 214D. Other means of accommodating thermal expansion may be used.
In one embodiment, instead of a collar/collet arrangement as described above, the force applied to the slugs 214D to tighten them against the bars 212D consists of one or more molybdenum alloy wires 250D (shown on FIG. 29B in white) wrapped around the outer edges of the slugs 214D. In one embodiment, four wires 250D are used, but other embodiments may use other numbers of wires 250D. The two ends of each molybdenum wire 250D are twist tied to one another, and the ends of the wires 250D may be cut off from the twisted portion. The one or more wires provide the force, and the molybdenum alloy provides for a limited amount of thermal expansion. As noted above, the force need not be particularly strong or exist at all until the assembly is heated. For example, the wires 250D may be only relatively loosely tied around the slugs 214D, providing little force until the slugs 214D are heated, although in other embodiments, the wires 250D apply force both before and during the heating process.
The rotor assembly 200D is then heated 120D in a furnace sufficiently to cause the slugs 214D to braise to the bars 212D. In one embodiment, the rotor assembly 200D is furnace-brazed in an atmosphere of 5% Hydrogen/95% Nitrogen (5% H₂/95% N₂) with a dew point at or above 25 degrees C. The 5% H₂atmosphere provides a reducing environment that acts as flux to assure complete alloying of the Copper and Silver throughout the braze joints.
It can be helpful to ensure that the Hydrogen percentage of the furnace-brazing atmosphere not exceed 5% H₂and the dew point be at or above 25 degrees C. Atmospheres with higher percentages of H₂and the dew points lower than 25 degrees C. may attack the surface insulation of the laminations on the discs 210D, which can significantly lower the surface insulation resistance increasing inter-laminar eddy current losses. Temperature may be measured at the point of the wires in the embodiment in which wires are used, or elsewhere in other embodiments.
The various forces applied as described above maintain the relative placement of the various components described above to maintain tight physical and electrical connections among them, while allowing for a limited amount of thermal expansion. If thermal expansion is not accommodated, the forces can cause the assembly to become misshapen in unpredictable ways. However, it can be helpful to have materials with a lower coefficient of thermal expansion used to apply forces, so as to tighten the assembly 200D as it is heated.
The rotor is then cooled 122D using a conventional annealing schedule. The collets 232D and collars 230D, bolts, including bolt 220D, springs and plates 222D used to apply the forces described above may be removed 124D. Step 124D may include milling, sanding or otherwise shaping the now braised slugs 214D and bars 212D, in order to shape them into a cylindrical shape. The milling can also remove the wires, which may braise onto the slugs 214D and bars 212D.
One or more Beryllium-copper bands are heated 126D to expand them and slipped 128D over the slugs 214D so that as the bands cool, they will exert a radial force towards the axis of the rotor. The assembly is allowed to reach room temperature 136D, compressing the one or more bands around the slugs 214D. If desired, before the bands are slipped over the rotor assembly 200D, as part of step 132D, at least the ends of the rotor assembly 200D are shrunk by chilling them. As the temperatures of the bands and the rotor approach equilibrium in step 136D, the bands are set onto the rotor assembly 200D with an interference fit.
The rotor assembly 200D can then be finished using conventional rotor components, and the finished rotor used to build 138D a conventional electric motor using conventional techniques. The electric motor including the rotor assembly 200D can be used to build 140D conventional products such as partially- or fully-electrically powered vehicles, such as electric or hybrid-electric automobiles, rockets, and the like.
FIG. 32 schematically illustrates a thermal management system 100E in accordance with a preferred embodiment of the invention. System 100E is comprised of four subsystems; power train cooling subsystem 101E, refrigeration subsystem 103E, battery cooling subsystem 105E, and heating, ventilation and cooling (HVAC) subsystem 107E. Each subsystem will now be described in detail.
Subsystem 101E is comprised of a continuous power train cooling loop 109E which is used to cool drive motor 111E, the vehicle's principal traction motor. Preferably cooling loop 109E is also used to cool various system electronic components 113E (e.g., the power electronics module for motor 109E). System electronics 113E are preferably mounted to a cold plate 115E which is used to transfer the heat away from the electronics and into the liquid coolant (i.e., the heat transfer medium) contained in the cooling loop. Cooling loop 109E also includes a pump 117E to circulate the coolant through the cooling loop, a radiator 119E for discharging the heat to the ambient atmosphere, and a coolant reservoir 121E. Preferably the system also includes a fan 123E for forcing air through radiator 119E when insufficient air is passing through the radiator to achieve the desired level of cooling, for example when the vehicle is not moving.
Refrigeration subsystem 103E is comprised of a compressor 125E, condenser 127E, fan 129E, thermostatic expansion valve 131E, heat exchanger 133E and dryer/separator 135E. Compressor 125E compresses the low temperature refrigerant vapor in the subsystem into a high temperature vapor. The refrigerant vapor then dissipates a portion of the captured heat when it passes through condenser 127E, thereby leading to a phase change from vapor to liquid, the liquid remaining at a high temperature and pressure. Preferably the performance of condenser 127E is enhanced by using a blower fan 129E. The liquid phase refrigerant then passes through thermal expansion valve 131E which lowers both the temperature and pressure of the refrigerant as well as controlling the flow rate of refrigerant into heat exchanger 133E. Heat exchanger 133E provides a simple means for transferring heat between the refrigerant contained in subsystem 103E and the coolants contained in the other subsystems. After being heated in heat exchanger 133E, the refrigerant is separated into the liquid and vapor phases by dryer/separator 135E, thus insuring that only vapor passes through compressor 125E. It should be appreciated that although refrigeration subsystem 103E is preferred, the invention can utilize other refrigeration subsystems as long as the utilized refrigeration subsystem includes a heat exchanger which can be used cooperatively with the other thermal subsystems of the vehicle as described herein.
Battery cooling subsystem 105E includes the energy storage system 137E (ESS) coupled to a coolant loop 139E containing the coolant (i.e., a heat transfer medium). In a typical electric vehicle, ESS 137E is comprised of a plurality of batteries. The coolant is pumped through ESS 137E, typically via a heat transfer plate (not shown) coupled to ESS 137E, by circulation pump 141E. During normal operation, the coolant contained in loop 139E is cooled via heat transfer with the refrigerant in heat exchanger 133E. Additionally, in a preferred embodiment of the invention, cooling loop 109E is also thermally coupled to a heater 143E (e.g., a PTC heater), thus insuring that the temperature of ESS 137E can be maintained within its preferred operating range regardless of the ambient temperature. Subsystem 105E also includes a coolant reservoir 145E.
Heating, ventilation and cooling (HVAC) subsystem 107E provides temperature control for the vehicle's passenger cabin. It includes a fan 147E which is used to circulate air throughout the cabin on demand, regardless of whether the air is heated, cooled, or simply fresh air from outside the vehicle. To provide cool air, circulating pump 149E circulates coolant contained within coolant loop 151E through radiator 153E, the coolant contained in loop 151E being cooled by heat transfer with the refrigerant in heat exchanger 133E. To provide warm air during normal vehicle operation, subsystem 107E is coupled to subsystem 101E via flow control valves 155E, 157E, and 159E, thus allowing the coolant heated by subsystem 101E to flow through radiator 153E. Additionally, in a preferred embodiment of the invention, a heater 161E (e.g., a PTC heater) is integrated within radiator 153E, thus allowing cabin heating prior to that achievable by subsystem 101E alone.
It will be appreciated that there are numerous ways of controlling the amount of cooling supplied by refrigeration subsystem 103E to the other subsystems. One approach is through the use of valves, for example a valve within coolant loop 139E can be used to control the flow of coolant through the battery cooling subsystem 105E and thus the level of cooling achieved via heat exchanger 133E. Similarly a valve within coolant loop 151E can be used to control the flow of coolant through HVAC subsystem 107E and thus the level of cooling achieved via heat exchanger 133E. Alternately, as both the battery cooling subsystem 105E and the HVAC subsystem 107E place a thermal load on heat exchanger 133E of refrigeration subsystem 103E, by simply varying the speed of the two coolant circulation pumps within these two subsystems, i.e., coolant pumps 141E and 149E, respectively, the level of cooling achieved by the two subsystems is continuously variable, thereby avoiding the necessity of valves within the coolant loops.
As will be understood by those familiar with the art, the present invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. Accordingly, the disclosures and descriptions herein are intended to be illustrative, but not limiting, of the scope of the invention which is set forth in the following claims.
FIG. 33 schematically illustrates the primary components of the rotor assembly cooling system of the invention. Rotor assembly 100F includes a rotor 101F fixed to a rotor drive shaft 103F. Drive shaft 103F is hollow and closed at end 105F and open at end 107F. Although not a requirement of the invention, preferably shaft 103F is hollow over the majority of its length, including that portion of the shaft in contact with rotor 101F, thereby insuring efficient cooling of the rotor assembly. A hollow coolant feed tube 109F is rigidly attached to shaft 103F with at least one, and preferably a plurality of support members 111F.
During operation, coolant is pumped into end 113F of feed tube 109F. The coolant flows through the length of feed tube 109F until it is redirected by the inside surface of closed end 105F of shaft 103F. The coolant than flows back along direction 115F towards the inlet, passing within the coolant flow region between the outer surface of feed tube 109F and the inside surface of shaft 103F thereby cooling the drive shaft and the attached rotor.
As both shaft 103F and feed tube 109F rotate, the assembly requires at least one coolant seal 117F to seal rotating shaft 103F, and at least a second coolant seal 119F to seal rotating feed tube 109F. It will be appreciated that seal 117F is more critical than seal 119F as coolant leaked from seal 119F will simply re-enter the coolant reservoir.
Support members 111F can take any of a variety of forms, a few of which are shown in the cross-sectional views of FIG. 34-38. The support member shown in FIG. 34 is comprised of a plurality of spokes 201F that rigidly couple feed tube 109F to shaft 103F. The support member shown in FIG. 35 also includes a plurality of spokes 301F, however in this support member the spokes are coupled to a pair of concentric rings 303F and 305F which are rigidly coupled to feed tube 109F and shaft 103F, respectively. Although the members shown in FIGS. 34 and 35 both utilize spokes, the member shown in FIG. 35 is generally easier to fabricate than the member shown in FIG. 34. It will be appreciated that a fewer or a greater number of spokes can be used with either of the support members shown in FIGS. 34 and 35.
FIG. 36 shows another alternate embodiment of the support member. In particular, member 401F is a ring-shaped member which includes a plurality of perforations 403F that provide the necessary coolant path. Member 401F can utilize fewer or greater numbers of perforations, different size perforations or perforations of varying size within a single member.
FIG. 37 shows another alternate embodiment of the support member. As shown, member 501F includes a plurality of slotted openings 503F. Preferably openings 503F are angled, thus allowing members 501F to provide an additional means for pumping the coolant as it passes through the region between feed tube 109F and shaft 103F. Although member 501F is shown with slanted slots, it should be understood that other shapes can be used in the slanted openings, for example slanted perforations. Additionally, member 501F can utilize fewer or greater numbers of openings than shown.
In addition to using a plurality of support members to couple feed tube 109F to shaft 103F, in at least one embodiment of the invention a continuous support member 601F is used, as illustrated in FIG. 38. As shown, member 601F is comprised of a continuous support strut which helically wraps around feed tube 109F and couples it to shaft 103F. Due to the helical shape of member 601F, coolant is actively pumped in the region separating feed tube 109F from shaft 103F, thus insuring continuous coolant flow to the rotor assembly.
In order to improve coolant flow when the coolant undergoes the directional change at the end of feed tube 109F, adjacent to end 105F of feed tube 103F, preferably the inside surface 701F of the end of feed tube 103F is shaped, for example as illustrated in FIG. 39. Shaping surface 701F promotes coolant flow and reduces flow stagnation. It will be appreciated that shaping surface 701F aids coolant flow regardless of the configuration used for the support member.
It should be understood that an electric motor utilizing the rotor assembly cooling system of the present invention is not limited to a specific implementation. FIG. 40 conceptually illustrates the basic elements of an electric motor utilizing the present invention. It will be appreciated that FIG. 40, as with the other figures included herein, is not drawn to scale.
The other elements of electric motor 800F are the same as in a conventional electric motor. For example, motor 800F includes a stator 801F, drive shaft bearings 803F and motor case 805F. The rotor cooling assembly, in addition to the other elements previously described in detail, also includes a coolant reservoir 807F within a housing 809F and a coolant pump 811F. In at least one embodiment, housing 809F also contains the transmission thus allowing the coolant to also be used to cool and lubricate the transmission. In at least one alternate embodiment, housing 809F is a separate housing used only for coolant containment and circulation, thus requiring the other end of the drive shaft to be coupled to the power train of the vehicle. It will be appreciated that the rotor cooling assembly of the invention can be used in conjunction with other cooling systems, for example a coolant system integrated into the motor housing.
As will be understood by those familiar with the art, the present invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. Accordingly, the disclosures and descriptions herein are intended to be illustrative, but not limiting, of the scope of the invention which is set forth in the following claims.
Referring to the drawings, an energy storage system 10G and methodology for balancing batteries within the energy storage system 10G is shown. The energy storage system (ESS) or battery pack 10G is generally comprised of a predetermined number of battery modules or sheets 12G, a main control and logic PCB 14G, and a 12 volt power supply 16G. In one embodiment contemplated the energy storage system 10G will have eleven battery modules or sheets 12G which is capable of producing approximately 375 volts DC. This nominal voltage will operate an electric vehicle that will be capable of traveling many miles without recharging and is capable of delivering enough power and acceleration to compare favorably with internal combustion engines. In one contemplated embodiment the battery pack 10G will be capable of storing enough energy such that the electric vehicle can travel approximately 200 miles without recharging. However, it should be noted that it is also contemplated to have an electric vehicle based on the present invention that can travel well over 200 miles without recharging. It is also contemplated in one embodiment that the electric vehicle using the battery pack 10G of the present invention will be capable of accelerating from zero to 60 miles per hour in approximately four seconds. No other electric car known has produced this type of acceleration and mileage range without recharging.
The present invention uses batteries 18G made of lithium ion cells. In particular, one embodiment uses commodity 18,650 form factor lithium ion cells for the electric vehicle. The batteries 18G in the present invention store the chemical energy equivalent of approximately two gallons of gasoline. The battery pack 10G operates at a nominal 375 volts and delivers approximately up to 240 horsepower to the motor. The energy and power capabilities of the battery pack 10G allow for the battery pack 10G design and architecture to have many features that ensure the safety of the vehicle and its occupants during the use of the electric vehicle. It should be noted that the lithium ion cells 18G are rechargeable such that after recharging, the batteries 18G will be able to provide traction power for the vehicle based upon a fully recharged and capable battery. The battery pack or energy storage system 10G in one embodiment comprises 6,831 individual lithium ion 18,650 cells that will allow for it to achieve the drive power and range necessary for the vehicle. These cells 18G are electrically connected in parallel groups of 69 cells wherein each of these groups of 69 cells constitutes an electric module called a brick 20G.
The bricks 20G are then connected in series within individual battery modules 12G in the energy storage system 10G called sheets 12G. Each sheet or battery module 12G is a single mechanical assembly and consists of nine bricks 20G electrically connected in series. It should be noted that it is contemplated that the sheets or battery modules 12G will be the smallest replaceable unit within the battery pack 10G. Each sheet or battery module 12G generally has a nominal voltage of approximately 35 volts DC. Furthermore, each of these sheets 12G contains a mechanical mounting system, battery monitoring hardware electronics, a cooling system, as well as various safety systems to ensure proper protection for the vehicle and occupants of such vehicle. In the embodiment contemplated eleven sheets 12G will be used in total to bring approximately 375 nominal volts DC to the ESS 10G for use in the electric car. Each of these sheets are rigidly mounted in an ESS enclosure 22G and electrically connected to one another in series. This series connection will create the nominal voltage of approximately 375 volts DC as described above. It should be noted that the ESS 10G contemplated and shown in the present invention has a nominal voltage of approximately 375 volts, however that voltage can be adjusted by either increasing or decreasing the number of sheets and/or boards within the ESS or battery pack 10G. Furthermore, each sheet 12G will also contain a fuse that is electrically in series. The ESS 10G will also generally include two normally open contactors 24G that are controlled by a watchdog computer, i.e., BSM or battery safety monitor 26G, that is also capable of shutting off high voltage to the rest of the vehicle in the case of a fault within the battery pack 10G. The ESS 10G also includes an auxiliary power system or APS 28G, a DC to DC converter, which provides 12 volt power to the rest of the vehicle. It should be noted that the entire system is contained inside an enclosure 22G which prevents access to any high voltage leads from occupants or users of the vehicle. In one embodiment contemplated the enclosure 22G is made of an aluminum material, however any other non conductive material may be used depending on the design requirements of the vehicle. The system 10G also includes a plurality of other components such as electrical hardware to monitor the battery 32G, a plurality of sensors to monitor the environment, a cooling system 30G and other safety features intended to create a safe environment for the occupants and users of the electric vehicle. It should be noted that when the contactors 24G within the ESS enclosure 22G are not energized by the battery safety monitor 26G and are in their normal or open state, there is no external high voltage access available outside of the ESS enclosure 22G in the electric vehicle.
The ESS 10G includes battery monitoring boards (BMB) 34G. A battery monitoring board 34G is associated with each sheet 12G of the battery pack 10G. The battery monitoring board 34G monitors the voltage levels and other parameters of all of the bricks 20G within its sheet 12G. As described above, nine bricks 20G are electrically connected in series within each sheet 12G. However, it should be noted that any other number of bricks 20G or sheets 12G may be used for the ESS or battery pack 10G of the present invention. The battery monitoring board 34G also is capable of connecting a small load to an individual brick 20G within its sheet 12G to bleed the brick voltage of that specific brick 20G to a lower level. It should further be noted that the battery monitoring boards 34G are networked to each other using a controller area network (CAN) bus. In an effort to more efficiently use the power provided by the ESS or battery pack 10G it is desirable to have all of the voltage levels of all of the bricks 20G within the battery pack 10G at the same voltage level. In the embodiment contemplated it is desirable to have each of the voltage levels of all bricks 20G within the battery pack 10G within a predetermined voltage delta (ΔV). In one embodiment contemplated the voltage delta is approximately 20 millivolts. However, the voltage delta may be within the range of one millivolt up to many volts depending on the design requirements for the battery pack 10G and the electric vehicle. There is a desirability to have the voltage levels of all bricks 20G match as closely as possible to one another to increase efficiency of the batteries and range of the electric vehicle, this is generally accomplished by balancing of the batteries.
The present invention includes a self balancing methodology or algorithm 40G for use in the battery pack or ESS 10G of the present invention. It should be noted that the methodology 40G can be used on any battery or battery system or pack not just those in vehicles. A general flowchart is shown in FIG. 46 for such a self balancing methodology 40G. As shown in FIG. 46, the methodology starts in box 42G where each of the battery monitoring boards 34G will periodically sample the voltage level of all of its bricks 20G at a predetermined interval. Then in box 44G the battery monitoring board 34G will determine the lowest brick voltage within its sheet 12G. The methodology then enters block 46G and sets or initializes each battery monitoring board 34G with a target balance voltage (TBV) value. Initially this target balance voltage value is set to the lowest brick voltage within the individual sheet 12G to which the battery monitoring board 34G is associated therewith. Therefore, each battery monitoring board 34G will take the voltage of each of the bricks 20G within its sheet or battery module 12G and determine which is the lowest brick voltage within its sheet 12G and use that lowest brick voltage as its initial target balance voltage value within the methodology. The methodology then in block 48G will send that voltage level via the CAN bus to all other battery monitoring boards 34G. This announcement of the voltage level of the lowest brick by one of the battery monitoring boards 34G, via the CAN bus, will allow all of the other battery monitoring boards 34G in this example the other ten, to receive such announcement of the voltage level of the lowest brick in this other battery monitoring board 34G. In box 50G upon receiving the announcement of the voltage level of the lowest brick in any of the other sheets 12G the receiving battery monitoring board 34G will compare the announced lowest brick voltage level to their own target balance voltage value stored within their sheet system. If the announced low brick voltage is lower than the target balance voltage then the target balance voltage will be replaced, by the methodology in box 52G, within the battery monitoring board 34G that received and processed the announced lowest brick voltage. This will ensure that all of the battery monitoring boards 34G will have the lowest brick voltage stored as the target balance voltage at all times across the entire battery pack 10G. If the announced low brick voltage is not lower than the battery monitoring boards 34G own stored target balance voltage then the stored target balance voltage will be kept as the low brick voltage within the system. The methodology then in box 54G will sample the voltages of all the bricks 20G. The methodology next will enter box 56G and compare the target balance voltage of each battery monitoring board 34G to the sampled voltages of the bricks 20G within the sheet 12G of each battery monitoring board 34G. The battery monitoring boards 34G will compare the sampled voltage of all of their bricks 20G to determine if that voltage is higher than the target balance voltage. If the target balance voltage is less than the sampled voltage then the methodology will determine if the sample voltage is outside of the voltage delta as described above. If the sampled voltage is outside the voltage delta the methodology has the battery monitoring board 34G issue a command to bleed the brick 20G having the higher voltage to a level where the voltage of the brick 20G matches or is within the voltage delta of the target balance voltage. The bleeding of the brick 20G occurs by applying a small load to the brick 20G to bleed the charge and ensure balancing between the bricks 20G of the battery pack or ESS 10G. It should be noted that after all of the bricks 20G are bled to the same general relative voltage value the methodology will return and continue sampling of the voltages across all boards as described above.
It should also be noted that safeguards are built into the methodology 40G to ensure proper use of the balancing algorithm within the ESS 10G. One of the safeguards will prevent a bricks 20G from being completely discharged. To protect against complete discharge the methodology will query whether the sampled voltage or target balance voltage is less than a fixed minimum voltage value. It should be noted that the minimum fixed voltage value can be any voltage between zero and 375 volts depending on the design requirements of the ESS system of the present invention. If the brick voltage being bled is equal to the fixed minimum voltage value the bleeding of the brick 20G will be stopped via commands from the balance monitoring board 34G. This will ensure that the brick 20G and battery cells 18G associated therewith are never completely discharged.
Furthermore, another safeguard that the methodology uses will allow it to monitor and recover from an anomalous announced low brick voltage or a low brick voltage announced by a battery monitoring board 34G that is no longer in the ESS and/or connected to the CAN bus. To prevent such occurrences each of the battery monitoring boards 34G will periodically replace its own target balance voltage with the lowest voltage from its own bricks 20G as the methodology shows in box 60G. This periodic replacement will occur at predetermined intervals and when an announced brick voltage that is less than or equal to the battery monitoring boards target balance voltage has not been received for a predetermined time interval. In one contemplated embodiment this time interval will be approximately 240 seconds. However, any other time interval may be used depending on the design requirements of the ESS 10G. It should be noted that the time intervals should be greater than the voltage announcement interval. In one contemplated embodiment the battery monitoring board announces its low brick voltage approximately every 120 seconds. However, it should be noted that any other time interval can be used depending on the design requirements for the ESS 10G. It should further be noted that in order to prevent all of the battery monitoring boards 34G from announcing their low brick voltages simultaneously the first announcement after booting of the system 10G is delayed by a predetermined amount of time based upon the battery monitoring boards 34G unique CAN identification or ID.
It should further be noted that voltage measurements may not be valid while the ESS 10G is being charged or discharged at high current during operation of the vehicle. As such balancing of the bricks 20G and batteries may be disabled by use of commands from an external microprocessor during such charging and discharging operations. If the voltage measurements are not valid the balancing becomes ineffective and at such time the external microprocessor will disable the balancing algorithm from operating. After the charging or discharging at high current is complete the external microprocessor will enable the balancing algorithm and methodology to continue. However, the system also will prevent the balancing methodology and algorithm from being permanently disabled by having the balancing algorithm only disabled for a specified time period that can be anywhere from a few milliseconds to many minutes depending on the charging or discharging at high currents occurring in the ESS 10G. It should further be noted that the self balancing methodology of the battery pack or ESS 10G will allow for balancing of the batteries to begin from the moment a battery monitoring board 34G is attached to a sheet 12G. Furthermore, if sheets 12G are connected or disconnected from each other balancing will automatically occur between the sheets 12G via announcement of the lowest brick voltage via the CAN within the vehicle electrical architecture.
The methodology also may include an alternate embodiment or implementation that will operate in the same general manner as the methodology described above. The alternate methodology, via the battery monitoring boards 34G, will first periodically sample the voltage level of all of its bricks 20G at a predetermined interval. The alternate methodology will next in box 44G compute, via the battery monitoring board 34G the highest brick voltage within its sheet 12G. Next the alternate methodology in block 46G will initialize the target balance voltage with the highest brick voltage found within its sheet 12G. Next in block 48G the battery monitoring board 34G will periodically at predetermined intervals send or announce its highest brick voltage. This announced highest brick voltage will be sent to all other battery monitoring boards 34G, via the CAN bus, within the entire battery pack 10G. Then in box 50G all of the other battery monitoring boards 34G will receive the announced highest target brick voltage from the sheet 12G of the battery monitoring board 34G which announced such voltage. Then the battery monitoring board 34G that receives such highest brick voltage will compare such level to their own target balance voltage value stored within their system and determine if the highest brick voltage just received is greater than the presently stored target balance voltage. In block 52G if the announced and received highest brick voltage is greater than the stored target balance voltage, the received target brick voltage will be used to replace the target balance voltage within the battery monitoring board 34G. This alternate methodology will then enter block 54G and sample the voltage of all of the bricks via the battery monitoring board 34G associated therewith. Next in block 56G the alternate methodology will compare the target balance voltage with the sampled brick voltages in each battery monitoring board 34G. The sample voltages will be compared to the target balance voltage to determine if the sampled voltage, of block 54G, is less than the target balance voltage stored in the battery monitoring board 34G. If the sample voltage is less than the target balance voltage and the sample voltage is outside of the voltage delta, as described above, the alternate methodology will adjust by raising the voltage or charging the brick 20G having the sampled voltage such that the voltage will be raised to that of the target balance voltage which is the highest brick voltage in the battery pack 10G. It should be noted that the second method for the highest brick voltage also includes safe guards to ensure that a maximum voltage for each brick 20G is not crossed by overcharging the brick 20G over the target balance voltage just as that described above for the other implementation of the lowest brick voltage target balance voltage. The alternate methodology will also include a timeout portion for the algorithm to periodically replace the target balance voltage if predetermined parameters are met and a predetermined amount of time passes with the TBV not being changed.
It should be noted that the alternate methodology that raises the voltage of the lowest brick up to the level of the highest brick is contemplated to be implemented by only using energy from other bricks in the sheet 12G or battery pack 10G and/or may be from other residual energy collected during operation of the vehicle. It should be noted that the alternate methodology of raising the voltage of the lowest brick up to the level of the highest brick may lead to a more efficient methodology and ESS 10G. This efficiency will be achieved through the use of energy being shifted and moved between bricks 20G and not bled as described in the methodology described above. Therefore, the redistribution of the energy among the bricks 20G will lead to a more efficient system and increased range of the vehicle. It should be noted that the sampling of voltages occur at intervals that will allow for a constant movement of the target balance voltage for the highest brick voltage of the battery pack 10G and/or sheet 12G to be constantly adjusted in either an upward or downward direction depending on the energy shift between battery bricks 20G during operation of the alternate methodology. Thus, if the lowest brick voltage is charged to the currently stored highest target balance voltage, such charging of the lowest brick voltage will shift energy from other bricks 20G within the sheet 12G or battery pack 10G thus generally lowering the highest target balance voltage a predetermined amount. The constantly changing highest target balance voltage will in effect shift the charge throughout the battery pack 10G such that the batteries remain in balance thus increasing efficiency and range of the electric vehicle. It should be noted that this second methodology may be used in any known vehicle and in any known system such as but not limited any system that uses batteries or any other known electrical system and is not limited to use in vehicles. Therefore, either the highest target balance voltage or lowest target balance voltage methodology as described herein may be used for any known system that uses batteries or battery packs to provide power to such system or the like.
Referring to the drawings, an electric vehicle communication interface 10H is disclosed. The electric vehicle communication interface 10H is for use in any type of vehicle including an automobile, boat, train, plane, or any other transportation vehicle. However, it is specifically designed for use in an all electric vehicle 12H. The all electric vehicle 12H will operate completely on battery power for all propulsion and other automotive related needs. The electric vehicle 12H of the present invention uses a battery pack made of sheets of cells of lithium ion batteries arranged in a predetermined pattern. This battery pack will allow for propulsion of the electric vehicle 12H some distance before recharge is necessary. It should also be noted that the electric vehicle communication interface 10H of the present invention may be used in any other type of automotive vehicle, such as internal combustion, hydrogen cell vehicle, hybrid vehicle, alternate fuel type vehicle, or any other type of compulsion system known for a vehicle. It should also be noted that the electric vehicle communication interface may be completely wireless or include hard wire portions for use in connecting components as described herein.
FIGS. 47 and 48 show the electric vehicle communication interface 10H according to one contemplated embodiment of the present invention. It should be noted that other contemplated embodiments for the connections necessary for the electric vehicle communication interface 10H may be possible. The electric vehicle communication interface 10H generally includes a communication device 14H arranged and installed within the electric vehicle 12H. The communication device 14H may be installed in any predetermined position within the electric vehicle 12H and may also be incorporated into the computer controlling the vehicle internal network. However, the communication device 14H may also be a stand alone device depending on the device requirements and environment in which the electric vehicle 12H will be used. Generally, the communication device 14H is a communication chip which may use an 802.11 protocol, cellular or other standard protocol which are all well known in the art. In one specific embodiment a communication chip 14H developed by CircumNav Network may be used for the communication device 14H of the present invention. The electric vehicle 12H uses a communication chip 14H that is capable of communicating via any known protocol such as TCP/IP, GPRS, or any other standard protocol. The communication chip 14H allows for communication with a network 16H that may be cellular, internet, satellite or any other type of network or with a wired or wireless access point 28H. After the initial communication with network 16H the methodology then sends a communication from the network 16H to a second network 18H or to the user or driver 20H of the vehicle, or to a utility company or the manufacturer of the electric vehicle communication hub or server 22H. The second network 18H may include a manufacturer server or utility company server or any other known type of network while the first network 16H may include any cell tower, computer network, satellite system or hard line such as a phone network or power line network. The user 20H will be capable of communicating with either the first network 16H, the second network 18H or directly with the vehicle 12H via any user interface device 24H. Contemplated user interface devices 24H may include but are not limited to mobile devices, such as cell phones, PDA's, handheld devices, desktop computers, laptop computers or any other communication device that is capable of producing email, IM, or any other communication device that is well known in the art. Some of these communications between the user interface devices 24H and either the first and second network 16H, 18H or the vehicle 12H may be performed via the code division multiple access standards (CDMA), the time division multiple access standards (TDMA), the global system for mobile communication standards (GSM), 802.11, BlueTooth, ZigBee, powerline communications including but not limited to HomePlug or Lonworks, a proprietary or standard communications protocol overlaid on existing charging communications equipment, a standard protocol such as CAN implemented on a custom physical layer, or any other standard protocol that is known in both wireless and hardwired configurations, for communication between any of the known user interface devices 24H and the first and second network 16H, 18H or the electric vehicle 12H directly.
If the 802.11 standard is chosen for use in the electric vehicle 12H, the user 20H of the vehicle may then need to install and use a wireless router or any other known wireless access point 28 to enable the router to accept login from the electric vehicle 12H to allow for communication between the user interface device 24H and the electric vehicle communication chip 14H which operates on the 802.11 standard. It should be noted that with the other standards or protocols contemplated for use, other specific needs such as wireless router, hardwired connections, or the like may be needed and are all contemplated for use if necessary depending on the design requirement of the electric vehicle communication interface 10H as used in the electric vehicle 12H.
The use of the communication chip 14H as described above in the electric vehicle 12H may allow for communication to the first network 16H to allow for the vehicle 12H to contact the user 20H via the user interface device 24H by any known mobile device or desktop, laptop, etc., via either email, instant messaging or any other known communication protocol. Also, it should be noted that the user or driver 20H of the vehicle is also capable of communicating with the electric vehicle 12H from their portable device such as a cell phone, PDA, laptop, personal computer, server, any known text messaging device, or any other communication device either directly with the vehicle 12H or through the first and second networks 16H, 18H to the vehicle to program and send specific instructions to the electric vehicle 12H for controlling and monitoring the battery system 26H arranged within the electric vehicle 12H. This communication between the electric vehicle 12H and user 20H or user 20H and electric vehicle 12H enables a plurality of scenarios through which the communication will have specific functions with respect to the propulsion system and other internal components of the electric vehicle 12H. In one contemplated controlling methodology for the communication interface 10H, the user 20H may be capable of querying or monitoring the electric vehicle's battery pack and cells 26H for its state of charge (SOC). This will allow the user 20H to determine if the battery 26H is capable of driving the distance the user 20H must travel, if the battery 26H has not been charging or if the battery 26H is charged to the level set by the user and capable of a maximum mileage trip based on the battery installed therein. Another contemplated methodology will have the electric vehicle 12H notifying the user or driver 20H that the battery 26H is fully charged and is ready for driving. Yet another methodology contemplated will have the vehicle 12H notifying the user or driver 20H that a problem occurred during charging of the battery 20H and that the maximum distance for travel for the electric vehicle 12H has been reduced or that the electric vehicle 12H needs immediate servicing and is not available for driving at the present time. Still yet another methodology contemplated for the electric vehicle communication interface 10H for the present invention will have the user or driver 20H of the electric vehicle requesting the electric vehicle 12H to initiate heating or cooling of the vehicle 12H along with initiate heating or cooling of the battery cells and associated battery pack 26H to prepare for driving of the electric vehicle 12H. This preparation may include adjusting the battery temperature based on the distance of the expected drive, the external temperature that the electric vehicle 12H will be used in, the weather in which the electric vehicle will be driven and/or any other parameters that effect the performance and durability of the battery 26H and hence the electric vehicle 12H in the driving environment. Still yet another methodology contemplated for use in the communication interface 10H of the present invention may have the user 20H capable of powering on and off in predetermined cycles and at predetermined times the charging of the battery 26H from a user interface device 24H. Furthermore, the user 20H may be capable of discharging the battery 26H into the electricity or electric grid of the locale in which the electric vehicle 12H is either charged or stored via a vehicle to grid application that will allow for communication between a local utility company server and the electric vehicle 12H, thus allowing for certain operations to be performed by the utility company and the user 20H on the electric vehicle 12H. Yet another use would be to alert the user or manufacturer that the battery 26H is falling below the minimum accepted storage levels (3.0V for example). Such discharge of the battery 26H may allow the user to plug in the vehicle or recharge the battery 26H by other means to preserve the battery 26H.
The vehicle to electricity grid applications and methodology may allow for the user 20H to either pre-register or associate with a local utility company or energy provider which will allow for the utility company to control the timing of charging or discharging of the electric vehicle 12H. This will allow the utility company during periods of high power consumption to have the option of turning off the charging of the electric vehicle 12H to help reduce the load on the electric grid controlled by the utility company and to avoid the sometimes necessary rolling blackouts. This also may allow for charging the vehicle 12H during periods of low power consumption by having the utility company to turn the charging of the electric vehicle 12H back on thus reducing the overall cost of operating the electric vehicle 12H by allowing for charging of the vehicle during periods of low power consumption which may result in lower kilowatts charges to the user of the electric vehicle 12H. It should be noted that the user 20H through the electric vehicle communication interface 10H and associated methodologies may be capable of having a preset operating command to automatically reject or accept such charging control or request for such from the utility company. This methodology would allow for the user 20H to override the utility company instruction of stopping charging because of high power consumption if the user 20H of the electric vehicle 12H needs the battery 26H charged at the current time in order to use the vehicle in the near future. It is contemplated that this type of mutual control between the utility company and the electric vehicle 12H may be executed via the internet using the 802.11 communication protocol or cell phone communication with the electric vehicle 12H by the user 20H or the utility company. It should also be noted that it is contemplated within this methodology that the utility company may also be capable of remotely querying and sampling the electric vehicles state of charge for the associated battery pack 26H and then send predetermined and specific instructions or requests to the electric vehicle and/or user to discharge electricity back into the grid via the vehicle to grid applications stored within the electric vehicle communication interface 10H. This will allow the user 20H to further reduce its cost by discharging electricity back into the electric grid of the utility company and hence receiving credits and the like.
The electric vehicle communication interface 10H also may include an in vehicle display 30H which may be any known display touch screen, screen, TV, tube or any other type of display device known. The dashboard display 30H may be arranged in any part of the vehicle 12H including but not limited to sun visors, heads up displays, anywhere in the instrument panel, anywhere in the seats, or any other position within the vehicle and it is even contemplated to have a touch screen on the outer surface of the vehicle. When the user or driver 20H of the electric vehicle 12H turns off the motor of the electric vehicle 12H, the user 20H may be prompted via the display device 30H in the vehicle 12H to choose or select one of a plurality of predetermined charging options for the electric vehicle battery pack 26H. It should be noted that the user 20H may also use a menu or voice controlled device that allows for selection of a next charge state at any time during use of the vehicle. In one contemplated embodiment there will be three separate charging options which will be displayed on the touch screen 30H display located in the vehicle's interior compartment. These charging options may include a boost charge which in theory is a full charge to the battery 26H of the electric vehicle 12H. By selecting the boost charge, the user 20H will be able to have maximum driving range such that the next time the user drives the electric vehicle 12H they can travel the maximum distance capable from the electric vehicle, however the boost charge may affect the durability and battery life of the battery pack 26H in the electric vehicle 12H over time. The second charging option displayed to the user or driver 20H of the electric vehicle 12H will be the regular charge option. The regular charge option generally will deliver a constant current charge up to a predetermined set voltage. The predetermined set voltage will be determined based on the battery pack system 26H and the configuration of the battery pack therein. It should be noted that a taper charge will not be used during the regular charge, which will result in the battery 26H not being completely charged after the regular charge option is chosen by the user. However, the regular charge will benefit the driver/user 20H of the vehicle 12H by allowing a quicker charge of the battery 26H and prolong battery life of the battery pack 26H in the electric vehicle 12H. However, the driving range will be reduced by a predetermined amount when selecting the regular charge option. In one contemplated embodiment the driving range will be reduced by about 4 to 10%. However, the reductions may generally be anywhere from 2% to 30% depending on the design requirements and batteries therein. The third option for one contemplated embodiment for charging of the battery pack 26H of the electric vehicle 12H will be a storage charge. This will allow the user 20H of the vehicle that does not plan to use the vehicle on a regular basis to maximize the life of the battery pack 26H. Generally, the storage charge is approximately a 30 to 50% charge. However, it should be noted that a range of 10 to 70% charge may also be used depending on the design requirements and environment in which the electric vehicle will be used. The storage charge will allow for the maximum life and durability of the battery pack system 26H in the electric vehicle 12H.
It should also be noted that the charging options may also include within its methodology a follow up menu that will allow the user or driver 20H of the vehicle 12H the choice of setting one of the predetermined charging options as the default such that every time the user exits the vehicle and begins charging of the battery pack 20H within the electric vehicle 12H such setting will be automatically used for charging thereof. It should also be noted that the methodology of charging options as discussed above may also be added to a keyfob such that the options are capable of being chosen via a keyfob that comes with the electric vehicle 12H. Furthermore, the options may also be added to a cell phone connection or other mobile device to follow the network connections of the first and second network 16H, 18H as described above to allow for choosing of one the charging options and setting any default via any user interface device 24H.
The communication chip 14H using the GPRS, which is a general packet radio service protocol, 802.11 standard, TCP/IP or any other standard protocol may communicate with a vehicle management system 32H which is the onboard computer that monitors, controls and coordinates various systems in the electric vehicle 12H including the power electronics module 34H, the energy storage system 26H and the HVAC system along with the user interface 30H. The communication chip 14H may also communicate with the wireless access point 28H or the power electronics module 34H. The energy storage system 26H, which is controlled by the vehicle management system 32H via