CN111902901B - Lithium ion battery - Google Patents

Abstract

The multi-core lithium ion battery includes a sealed housing and a support member disposed within the sealed housing. The sealed housing may be made to have a clamshell configuration. The sealed enclosure may further comprise at least two support members housed in separate compartments separated by a common wall. The support member includes a plurality of cavities and a plurality of lithium ion core members disposed within the plurality of cavities. The battery may further include a plurality of cavity liners, each cavity liner being located between a corresponding one of the lithium ion core members and a surface of a corresponding one of the cavities. A clamshell configuration may be used to form an airtight enclosure. Structures may be included in close proximity or contact with the lithium ion core member to control gas/fluid flow therefrom.

Description

Lithium ion battery

Technical Field

The present invention relates to lithium ion batteries, and more particularly, to a multi-core lithium ion battery having improved safety and reduced manufacturing costs.

Background

Due to the continued development of applications such as electric vehicles and grid storage systems, as well as other multi-cell battery applications such as electric bicycles, uninterruptible power battery systems, and lead-acid replacement batteries, the demand for electrochemical power batteries such as lithium ion batteries is also increasing. For these applications, high energy and power densities are required, but it is equally important, and even higher, to reduce manufacturing costs and improve safety to achieve a wide range of commercial applications. It is further desirable to adapt the energy/power ratio of these batteries to the energy/power ratio of the application.

For grid storage and electric vehicles for large applications, multiple cells connected in series and parallel arrays are required. Battery suppliers are concerned with both large cells (defined herein as greater than 10Ah per cell (ampere hours), and small cells (defined herein as less than 10h), large cells containing stacked or laminated electrodes, such as prismatic or polymer cells, are produced by LG Chemical, AESC, ATL and other suppliers Small cells (such as 18650 or 26650 cylindrical cells) or prismatic cells (such as 183765 or 103450 cells) and other similarly sized cells are produced by Sanyo, Panasonic, EoneMari, Boston-Power, Johnson Controls, Saft, BYD, Gold Peak and other suppliers.

Existing small and large batteries have some significant disadvantages. For small batteries, such as 18650 batteries, they have the disadvantage of being generally constrained by a housing or "metal container", which is partially mechanically stressed or deficient in electrolyte, resulting in a battery with a short cycle life and calendar life. As the lithium ion battery is charged, the electrodes swell. Due to the metal container, the jelly roll structure of the electrode is constrained and mechanical stresses can occur in the jelly roll structure, which limits its lifetime. As more and more storage capacity is required, more active anode and cathode materials are inserted into a given volume of metal container, which will subject the electrodes to greater mechanical stress.

In addition, the ability to increase the amount of electrolyte in small cells is limited, and the movement of the electrodes pushes the electrolyte out of the jelly roll as lithium is intercalated and deintercalated. This can lead to electrolyte starvation of the electrodes, such that lithium ion concentration gradients occur during power consumption and the electrodes dry out, forming side effects and dry areas that block ion paths, thereby reducing battery life. To overcome these problems, especially for long-life batteries, users must reduce performance by reducing the state of charge, limiting the available capacity of the battery, or reducing the charge rate.

Mechanically, small cells are difficult and costly to assemble into large arrays. Complex welding patterns must be created to minimize the possibility of weld failure. Solder failure can reduce capacity and create potential heating at the problematic solder connections. The more cells in the array, the higher the risk of failure and the lower the manufacturing yield. This means higher manufacturing and warranty costs. There are also potential safety issues associated not only with the failure of welds and internal short circuits, but also with the packaging of small batteries. Proper packaging of small cells is required to avoid cascading thermal runaway due to failure of one cell. Such packaging leads to increased costs.

For large batteries, the disadvantages are mainly safety, low volume ratio and gravimetric capacity and expensive manufacturing methods. Large batteries with large area electrodes have a lower manufacturing yield than small batteries. If there is a defect on the electrode of the large-sized battery, more material is wasted and the overall yield is reduced compared to the manufacture of the small-sized battery. Taking a 50Ah battery as an example, it is compared with a 5Ah battery. Defects in the 50Ah cell can result in 10 times more material loss than in the 5Ah cell, even though defects in both manufacturing methods only occur each time 50Ah occurs in the manufactured cell.

Another problem with large batteries is safety. The energy released in a battery entering a thermal runaway state is proportional to the amount of electrolyte that resides inside the battery and is accessible in the event of a thermal runaway. The larger the cell, the more free space for the electrolyte to fully saturate the electrode structure. Since the mass per Wh of electrolysis of large cells is typically larger than small cells, large cells are typically more powerful systems during thermal runaway and therefore less safe. Naturally, any thermal runaway will depend on the particular situation, but in general, the more fuel (electrolyte) the more intense the fire is when a catastrophic event occurs. In addition, once a large battery is in a thermal runaway mode, the heat generated by the battery may cause a thermal runaway reaction in an adjacent battery, thereby causing a cascade effect, igniting the entire battery pack, and seriously damaging the battery pack and surrounding devices, resulting in an unsafe condition for users.

When comparing the performance parameters of small and large batteries, it can be seen that small batteries generally have higher weight ratio (Wh/kg) and volume ratio (Wh/L) capacities than large batteries. It is easier to group multiple small cells using binning techniques to achieve capacity and impedance to match the overall distribution of production runs in a more efficient manner than large cells. This can improve the production yield during mass production of the battery pack, and in addition, it is easier to arrange small-sized batteries in an array having a small volume, thereby limiting the cascade runaway reaction of the battery pack, for example, caused by a short circuit inside one battery cell (the most common problem in the field of safety problems). Furthermore, the use of small cells has cost advantages, since high-volume production methods are well established in the industry and the failure rate is low. Machines are readily available, and their cost has been driven off of the manufacturing system.

On the other hand, large batteries have the advantage that the battery pack OEM is simple to assemble, has a more robust, large format structure, typically has room to place common, easy-to-use electromechanical connectors, has a significantly smaller number of battery cells, can be efficiently packaged and manufactured, does not have to address the various problems required to assemble small arrays of batteries, and does not have to have the expertise associated with them.

In order to take advantage of the use of small cells to manufacture cells that are larger in size, higher in power/energy capacity, but better in safety, and less expensive to manufacture than large cells, the assembly of small cells by a multi-core (MC) cell structure has been developed.

One such MC battery structure developed by BYD Company ltd uses an array of MCs integrated into a container made of metal (aluminum, copper alloy or nickel chromium). This array is described in the following documents: EP 1952475 AO; w02007/053990; US2009/0142658 Al; CN 1964126 a. The BYD structure has only metal material surrounding the MC and therefore has disadvantages in the event of a mechanical impact that causes a sharp object to penetrate the core and cause a local short circuit. Since all of the cores are placed in a common container (rather than being contained in a single metal container) with the electrolyte shared between the cores, any single failure caused by manufacturing defects or external abuse can propagate to the other cores and destroy the MC structure. Such batteries are not safe.

A method for preventing thermal runaway in an assembly of a plurality of electrochemical cells is described in US2012/0003508 a 1. In the MC structure described in this patent application, the individual cells are connected in parallel or in series, each cell having a jelly roll structure housed in its own metal container. The individual cells are then inserted into a container containing a rigid foam (including a flame retardant additive). These safety measures are costly to manufacture and limit the energy density, in part because of the cost of the mitigation materials.

Another MC structure is described in patent applications US2010/0190081 a1 and WO2007/145441 a1, which disclose the use of two or more stacked secondary batteries having a plurality of battery cells that provide two or more voltages through a single battery. In this arrangement, the cells are connected in series within the housing and use a separator. The series element forms only a high-voltage battery cell, but cannot solve any safety or cost problems, as compared to a conventional stacked-type single-voltage battery.

These MC-type cells offer certain advantages over large cells; however, they still have certain drawbacks in terms of safety and cost.

Disclosure of Invention

The present disclosure provides a novel MC type lithium ion battery structure having reduced production costs and improved safety while providing advantages in terms of larger battery size, such as ease of assembly of an array of such batteries, and the ability to meet power to energy ratios.

A multi-core lithium ion battery is described having a sealed enclosure within which a support member is disposed. The support member includes a plurality of cavities and a plurality of lithium ion core members disposed within respective ones of the plurality of cavities. There is a plurality of cavity liners, each cavity liner being located between a respective one of the lithium ion core members and a surface of a respective one of the cavities. The support member includes a kinetic energy absorbing material, and the kinetic energy absorbing material is formed of one of foamed aluminum, ceramic, and plastic. The cavity liner is formed of a plastic material and the plurality of cavity liners are formed as part of a monolithic liner member. There is also an electrolyte contained within each core, the electrolyte including at least one of a flame retardant, a gas generant, and a redox shuttle. Each lithium ion core member includes an anode, a cathode, and a separator disposed between each anode and cathode. Also included within the housing is an electrical connector that electrically connects the core member to electrical terminals external to the sealed housing. The electrical connector includes two bus bars, a first bus bar interconnecting the anode of the core member to a negative terminal member of a terminal located outside the housing, and a second bus bar interconnecting the cathode of the core member to a positive terminal member of the terminal located outside the housing.

In another aspect of the present disclosure, a divided enclosure for a lithium ion battery is provided that includes at least two parallel and/or series-connected support members that house a lithium ion core member. An exemplary lithium ion core member for housing in the disclosed support member takes the form of a jellyroll having a cylindrical (or substantially cylindrical) shape. The divided enclosure further includes at least one common wall for separating the first and second compartments from each other. The first/second compartment may define a shared atmosphere (atmosphere) across the two compartments, or a common wall may be used to define a unique/separate atmosphere in each compartment, i.e. a common wall is used to define a first airtight region in the first compartment and a second airtight region in the second compartment.

In implementations of the invention in which the common wall of the partitioned enclosure defines a shared atmosphere across the first/second compartments, the disclosed partitioned enclosure may advantageously include at least one pressure cutoff device/feature in communication with the shared atmosphere. Thus, in an exemplary embodiment, a single pressure cutoff device/feature may be provided that may effectively provide a pressure cutoff function for the first and second compartments.

In implementations of the present disclosure in which a common wall of the partitioned housing defines different first/second compartments, multiple pressure disconnects/features may be advantageously provided, namely a first pressure disconnect/feature for the first compartment and a second pressure disconnect/feature for the second compartment.

In another aspect of the present disclosure, the core members are connected in parallel or in series. Alternatively, the first group of core members are connected in parallel, the second group of core members are connected in parallel, and the first group of core members and the second group of core members are connected in series. The support member is in the form of a honeycomb structure. The kinetic energy absorbing material includes a compressible medium. The housing includes a wall having a compressible element that causes an electrical short circuit of the lithium ion battery when compressed by a force impacting the wall. The cavity in the support member and its corresponding core member are one of cylindrical, rectangular and prismatic. At least one cavity and its corresponding core member have a different shape than the other cavities and their corresponding core members.

In another aspect of the present disclosure, the at least one core member has a high power characteristic and the at least one core member has a high energy characteristic. The anodes of the core members are formed of the same material, and the cathodes of the core members are formed of the same material. Each separator member includes a ceramic coating, and each anode and each cathode includes a ceramic coating. At least one of the core members includes one of the anode and the cathode having a thickness different from the thickness of the anode and the cathode of the other core member. At least one cathode includes at least two materials of the group of compounds a through M materials. Each cathode includes a surface modifier. Each anode comprises one of Li metal or carbon or graphite. Each anode comprises Si. Each core member includes a wound anode, cathode and separator structure, or each core member includes a stacked anode, cathode and separator structure.

In another aspect of the present disclosure, the core members have substantially the same capacitance. At least one core member has a different capacitance than the other core members. At least one core member is optimized for power storage and at least one core member is optimized for energy storage. Further comprising a tab for electrically connecting each anode to a first busbar and a tab for electrically connecting each cathode to a second busbar, wherein each tab comprises means for interrupting the current through each said tab when a predetermined current is exceeded. The first busbar comprises a fuse element near each interconnection point between the anode and the first busbar and the second busbar comprises a fuse element near each interconnection point between the cathode and the second busbar for interrupting the current through said fuse element when a predetermined current is exceeded. A protective sleeve is also included surrounding each core member, and each protective sleeve is disposed outside of the cavity containing its respective core member.

In yet another aspect of the present disclosure, there is a sense line electrically interconnected with the core member, the sense line configured to allow electrical monitoring and balancing of the core member. The sealed enclosure includes a flame retardant member, and the flame retardant member includes a flame retardant mesh material attached outside the enclosure.

In another embodiment, a multi-core lithium ion battery is described that includes a sealed housing. A support member is disposed within the sealed enclosure, the support member including a plurality of cavities, wherein the support member includes a kinetic energy absorbing material. There are a plurality of lithium ion core members disposed within respective ones of the plurality of cavities. Further comprising a plurality of cavity liners, each cavity liner being located between a respective one of the lithium ion core members and a surface of a respective one of the cavities. The cavity liner is formed of a plastic material and the plurality of cavity liners are formed as part of a monolithic liner member. The kinetic energy absorbing material is formed of one of foamed aluminum, ceramic, and plastic.

In another aspect of the disclosure, there is an electrolyte contained within each core, and the electrolyte includes at least one of a flame retardant, a gas generant, and a redox shuttle. Each lithium ion core member includes an anode, a cathode, and a separator disposed between each anode and cathode. Also included within the housing is an electrical connector that electrically connects the core member to electrical terminals external to the sealed housing. The electrical connector includes two bus bars, a first bus bar interconnecting the anode of the core member to a negative terminal member of a terminal located outside the housing, and a second bus bar interconnecting the cathode of the core member to a positive terminal member of the terminal located outside the housing. The core members are connected in parallel. The core members are connected in series. The lithium ion battery may include a first group of core members connected in parallel and a second group of core members connected in parallel, and the first group of core members may be connected in series with the second group of core members.

In another aspect, the support member is in the form of a honeycomb structure. The kinetic energy absorbing material includes a compressible medium. The lithium housing includes a wall having a compressible element that causes an electrical short circuit of the lithium ion battery when compressed by a force impacting the wall. The cavity in the support member and its corresponding core member are one of cylindrical, rectangular and prismatic. At least one cavity and its corresponding core member have a different shape than the other cavities and their corresponding core members. At least one core member has a high power characteristic, and at least one core member has a high energy characteristic. The anodes of the core members are formed of the same material, and the cathodes of the core members are formed of the same material. Each separator member includes a ceramic coating, and each anode and each cathode includes a ceramic coating. At least one of the core members includes one of the anode and the cathode having a thickness different from the thickness of the anode and the cathode of the other core member.

In yet another aspect, the at least one cathode includes at least two materials of the group of compounds a through M materials. Each cathode includes a surface modifier. Each anode comprises Li metal, carbon, graphite or Si. Each core member includes a wound anode, cathode and separator structure, or each core member includes a stacked anode, cathode and separator structure. The core members have substantially the same capacitance. Wherein at least one core member has a different capacitance than the other core members. At least one core member is optimized for power storage and at least one core member is optimized for energy storage.

In another aspect of the present disclosure, a tab for electrically connecting each anode to a first bus bar and a tab for electrically connecting each cathode to a second bus bar are also included, wherein each tab includes means for interrupting the flow of current through each said tab when a predetermined current is exceeded. The first busbar comprises a fuse element near each point of interconnection between the anode and the first busbar, near each point of interconnection between the cathode and the second busbar, for interrupting the current through said fuse element when a predetermined current is exceeded. A protective sleeve is also included surrounding each core member, and each protective sleeve is disposed outside of the cavity containing its respective core member.

In another embodiment of the present disclosure, there is a sense line electrically interconnected with the core member, the sense line configured to allow electrical monitoring and balancing of the core member. The sealed enclosure includes a flame retardant member, and the flame retardant member includes a flame retardant mesh material attached outside the enclosure.

In another embodiment, a multi-core lithium ion battery is described that includes a sealed enclosure having a lithium ion battery region and a shared atmosphere region inside the enclosure. A support member is disposed within the lithium ion battery region of the sealed enclosure, the support member including a plurality of cavities, each cavity having an open end that opens into the shared atmosphere region. There is a plurality of lithium ion core members, each having an anode, a cathode disposed within a respective one of a plurality of cavities, wherein the anode and the cathode are exposed to a shared atmosphere region through open ends of the cavities, and the anode and the cathode are surrounded by the cavities substantially along their lengths. The support member includes a kinetic energy absorbing material. The kinetic energy absorbing material is formed of one of foamed aluminum, ceramic, and plastic.

In another aspect, there is a plurality of cavity liners, each cavity liner being located between a respective one of the lithium ion core members and a surface of a respective one of the cavities. And the cavity liner is formed of a plastic material. The plurality of cavity liners are formed as part of a monolithic liner member. There is also an electrolyte contained within each core, the electrolyte including at least one of a flame retardant, a gas generant, and a redox shuttle. Each lithium ion core member includes an anode, a cathode, and a separator disposed between each anode and cathode. Also included within the housing is an electrical connector that electrically connects the core member to electrical terminals external to the sealed housing. The electrical connector includes two bus bars, a first bus bar interconnecting the anode of the core member to a negative terminal member of a terminal located outside the housing, and a second bus bar interconnecting the cathode of the core member to a positive terminal member of the terminal located outside the housing.

In yet another aspect, the core members are connected in parallel or the core members are connected in series. Alternatively, the first group of core members are connected in parallel, the second group of core members are connected in parallel, and the first group of core members and the second group of core members are connected in series.

In another embodiment, a lithium ion battery is described that includes a sealed enclosure and at least one lithium ion core member disposed within the sealed enclosure. The lithium ion core member has an anode and a cathode, wherein the cathode includes at least two compounds selected from the compounds a to M. There is only one lithium ion core member. The sealed enclosure is a polymeric bag or the sealed enclosure is a metal can. Each cathode includes at least two compounds selected from compounds B, C, D, E, F, G, L and M, and further includes a surface modifier. Each cathode includes at least two compounds selected from compounds B, D, F, G and L. The battery is charged to a voltage higher than 4.2V. Each anode comprises one of carbon and graphite. Each anode comprises Si.

In yet another embodiment, a lithium ion battery is described having a sealed enclosure and at least one lithium ion core member disposed within the sealed enclosure. The lithium ion core member has an anode and a cathode. An electrical connector within the housing electrically connects the at least one core member to an electrical terminal external to the sealed housing; wherein the electrical connector comprises means for interrupting the current through the electrical connector when a predetermined current is exceeded. The electrical connector includes two bus bars, a first bus bar interconnecting the anode of the core member to a negative terminal member of a terminal located outside the housing, and a second bus bar interconnecting the cathode of the core member to a positive terminal member of the terminal located outside the housing. The electrical connector also comprises a tab for electrically connecting each anode to the first busbar and a tab for electrically connecting each cathode to the second busbar, wherein each tab comprises means for interrupting the current through each said tab when a predetermined current is exceeded. In the electrical connector, the first busbar includes a fuse element near each interconnection point between the anode and the first busbar, and the second busbar includes a fuse element near each interconnection point between the cathode and the second busbar for interrupting a current through the fuse element when a predetermined current is exceeded.

In another aspect, the housing is manufactured using a clamshell construction in which symmetrically identical sidewall components are joined together along a pair of seams to define the entire housing. The flip member may be made of plastic or ceramic material, but may also be made of metal. The flip construction can save costs by greatly reducing manufacturing/assembly operations.

In another aspect, one or more blanket-like structures may be provided within the disclosed enclosure. The blanket structure is typically configured and dimensioned to be positioned adjacent to the electrochemical element, e.g., on top of the open jellyroll, so that any gas/fluid flowing into or out of the electrochemical element encounters the blanket structure. Thus, the blanket structure may advantageously function to substantially limit the amount of hot particulate residues (e.g., liquid electrolyte and electrolyte gases) that may be emitted from the electrochemical cells due to undesirable interactions with adjacent electrochemical cells/jelly rolls. The blanket structure may have the following features: that is, axial gas flow relative to the blanket structure is facilitated, but lateral (e.g., side-to-side) flow therein is significantly reduced. Thus, according to an exemplary embodiment, the gas and/or other fluid expelled by the electrochemical element/jellyroll is preferably directed in a substantially axial manner through the blanket-like structure to the atmosphere area defined thereabove. When the pressure within the atmospheric region exceeds an applicable pressure threshold, a venting mechanism associated with the present disclosure may be activated, thereby venting gas from the enclosure to the external environment.

Additional features, functions and benefits of the present disclosure will become apparent from the detailed description which follows, particularly when read in conjunction with the appended drawings.

Drawings

The disclosure will be better understood from reading the following description, given purely by way of non-limiting example and with reference to the accompanying drawings, in which:

fig. 1A is an exploded perspective view of a multi-core lithium ion battery according to the present disclosure;

fig. 1B is a cross-sectional view of a multi-core lithium ion battery according to the present disclosure;

FIG. 1C is a stress-strain graph of an exemplary energy absorbing material of a support member according to the present disclosure;

fig. 1D is a cross-sectional view of another embodiment of a multi-core lithium ion battery according to the present disclosure;

FIG. 2 is a top view of a plurality of support member configurations according to the present disclosure;

fig. 3 is a perspective view of another embodiment of a multi-core lithium ion battery according to the present invention;

FIG. 4 is a perspective view of another embodiment of a support member having mixed rectangular and cylindrical cavities according to the present disclosure;

FIG. 5 is a perspective view of a prismatic wound and stacked core member according to the present disclosure;

fig. 6A shows MC lithium ion batteries connected in parallel/series according to the present disclosure;

fig. 6B is a perspective view of a parallel/series connected MC lithium ion battery according to the present disclosure;

FIG. 7 is a top view of a modular housing according to the present disclosure;

fig. 8 is an exploded perspective view of a MC lithium ion battery according to the present disclosure;

fig. 9A is a cross-sectional view of an egg-box shaped wall of a housing according to the present disclosure;

FIG. 9B is a cross-sectional view of the egg-box shaped wall of the housing during mechanical impact to the wall according to the present disclosure;

fig. 10A is a perspective view of a modular clamshell housing according to the present disclosure;

fig. 10B is an exploded perspective view of a modular clamshell housing according to the present disclosure;

fig. 11 is an exploded perspective view of a modular clamshell housing according to the present disclosure;

fig. 12A is a perspective view of a modular clamshell housing according to the present disclosure;

fig. 12B is an exploded perspective view of a modular clamshell housing according to the present disclosure; and

fig. 12C is an exploded perspective view of a modular clamshell housing according to the present disclosure.

Detailed Description

Multi-core array

In fig. 1A and 1B, a multi-core (MC) array 100 of lithium ion core members 102a-j having a jellyroll structure and a cylindrical shape is shown. Various shapes and sizes of ionic core members may be used in conjunction with the present disclosure, and specific shapes and sizes are described below. A set of conductive tabs 104 having a cathode connected to each core member 102a-j and a set of conductive tabs 106 connected to an anode of each core member 102 a-j. Tab 104 is also connected to cathode bus bar 108 and tab 106 is connected to anode bus bar 110. The cathode tabs 104 and anode tabs 106 are welded to the bus bars 108, 110 using spot welding or laser welding techniques. The bus bars 108, 110 are connected to a positive terminal 112 and a negative terminal 114, respectively, outside the MC enclosure 116. In this configuration, all of the ion core members 102a-j are connected in parallel, but it will be apparent to those skilled in the art that they may be connected in series or in other configurations.

The MC enclosure 116 of fig. 1B is hermetically sealed. The support structure 120 may be part of the housing 116 or may be a separate part configured to receive the ionomeric component at sufficient spacing so that limited expansion may occur during charge and discharge reactions to prevent mechanical interaction of the respective ionomeric components. Preferably, the housing 116 is made of a plastic or ceramic material, but may also be made of metal. If metal is used, bare steel is not preferred and any steel container needs to be coated with an inert metal (e.g., nickel). Preferred metals are aluminum, nickel or other metals that are inert to the chemicals used. Many types of plastics and ceramics can be used, provided that they are inert to the chemical and electrochemical environment. Examples of plastics and ceramics are polypropylene, polyethylene, alumina, zirconia. The housing 116 may include a fire retardant mesh attached to the exterior of the housing in order to prevent fire from reaching the interior of the housing.

Within the housing 116, in the lithium ion core region 118, there is an electrically insulating support member 120, which may be made of ceramic, plastic (e.g., polypropylene, polyethylene), or other material (e.g., aluminum foam). The support members 120 must have sufficient deformability/compressibility to protect the core member from damage in the event of an impact. In addition, the thermal conductivity needs to be made application-friendly by: that is, heat is dissipated during battery charging and discharging, thereby generating a uniform temperature distribution; and heat dissipation during catastrophic failure (e.g., internal short circuit causing thermal runaway of one core member). Proper heat dissipation characteristics can limit the chance of a cascade between cores going out of control. The support member may also absorb electrolyte, which may be confined in the support member if the electrolyte is expelled during abuse of the core member.

A support member 120 that is deformable and can absorb kinetic energy is particularly desirable because it distributes the impact load over a larger area, thereby reducing the amount of localized deformation at each core member 102a-j and reducing the likelihood of electrical shorting. Examples of kinetic energy absorbing materials are foams (e.g., aluminum foam, plastic foam), porous ceramic structures, honeycomb or other open structures, fiber filled resins, and phenolic materials. Examples of fibrous fillers for plastics and resin materials may be glass fibres or carbon fibres. Examples of aluminum-containing energy absorbers are aluminum foams having open or closed cells, aluminum honeycomb structures, and engineered materials (e.g., Altucore)^TMAnd CrashLite^TMMaterial). When the support member collapses during impact, collision or other mechanical abuse, it is important to protect the core from being punctured as much as possible to avoid internal mechanical shorts. This will create a more secure structure.

Energy absorbers are a class of materials that generally absorb mechanical kinetic energy by compressing or flexing at a relatively constant stress over a long distance, and without rebounding. The spring has a somewhat similar function, but springs back, and is therefore an energy storage device, not an energy absorber. Once the applied stress exceeds the "crush plateau" of the kinetic energy absorbing material (see 150 of FIG. 1C), the energy absorber will begin to crush approximately 50-70% of the material stress at a fairly constant stress. This expanded portion of the stress/strain curve defines the behavior of an ideal energy absorber. In this region, the area under the curve represents the product of stress and strain, or "work". In a practical energy absorber mass of limited size (e.g., support member 120), it is expressed as:

force x displacement

It will be appreciated that

Force (pound) x displacement (foot) ═ work (foot pound)

And

work (foot pound) as kinetic energy (foot pound)

The work required to compress support member 120 is equivalent to the kinetic energy of the mass that may impact support member 120. When designed to have an appropriate thickness and compressive strength, as will be apparent to those skilled in the art, the support member 120 may be made of kinetic energy absorbing materials that can absorb all of the kinetic energy of an impacting battery, such as in an electric vehicle crash. Most importantly, the cargo in the support member 120 (i.e., the lithium ion core members 102a-j) will never withstand forces higher than the compressive strength of the material (defined below). Thus, by absorbing the energy of the impacting mass at a constant force over a controllable distance, the protected structure (i.e., li-ion core members 102a-j) will not have to withstand the concentrated high energy/high force impacts that can result in catastrophic consequences that occur when the mass directly impacts the structure.

When a load is applied to a structure made of an energy-absorbing material, the load will first yield elastically according to the young's modulus equation. However, at about 4-6% strain (152 of FIG. 1C) in this particular A1 foam example, depending on the structural dimensions, the foam will begin to bend and continue to collapse under relatively constant stress. Depending on the initial relative density of the material, this constant collapse will proceed to about 50-70% of the strain (154 of FIG. 1C) for this Al foam material. At this point, the stress/strain curve will begin to rise as the energy absorbing material enters the "densification" stage. The point at which the material transitions from the elastic deformation phase to the plastic deformation phase in the stress/strain curve defines the "compressive strength" of the material.

The longer and relatively flat portion of the curve is between 4-6% transition and 50-70% of strain (covering about 45-65% of the possible strain value of the material), referred to as the "crush plateau". The only property of the kinetic energy absorbing material is that it is very useful for absorbing the kinetic energy of the impact mass while protecting the cargo being carried.

To further protect the core member, a cylindrical material made of metal, ceramic or plastic may be added around the core structure as the sleeve 121 of fig. 1A. The sleeve may be applied either directly around each core, outside the lining material, or inside the cavity structure in the support member. This prevents sharp objects from penetrating the core. Although only one sleeve is shown in the figures, it will be readily understood that a sleeve may be included for each core member.

The support member 120 may alternatively be designed with an open area 160, as shown in fig. 1D, that contains a filler material 162. Examples of filler materials are irregularly or regularly shaped media, which may be hollow or dense. Examples of hollow media are metal, ceramic or plastic spheres, which can compress under various pressures and act as impact-protecting energy absorbers. Specific examples are hollow aluminum spheres, ceramic grinding media of alumina or zirconia, and hollow polymer spheres.

The support member 120 may also be optimized to quickly transfer heat throughout the support member and uniformly distribute heat throughout the battery or limit thermal exposure between the cores when one core experiences thermal runaway due to abuse. In addition to improving safety, this may also extend battery life by limiting the maximum operating temperature and leaving the battery without any or passive thermal management. Most importantly, the thermal characteristics of the support members 120 help prevent failure from propagating from a failed core member to other core members, as the heat transfer properties of the material are optimized and can disrupt flame propagation. Since the material is also absorbent, it can absorb leaking electrolyte into the material, helping to reduce the severity of catastrophic failure.

The support member 120 improves the overall safety of the MC battery by: a) allowing the distribution of the ionic core members 102a-j to optimize the safety and high energy density of the battery, b) preventing rapid thermal propagation of the ionic core members 102a-j while dissipating heat; c) providing a protective collision and impact absorbing structure for the ionic core members 102a-j and reactive chemicals, and d) using widely recognized fire-blocking materials through fire-blocking.

Cylindrical cavities 122 are formed in the support member 120 for receiving the lithium ion core members 102a-i, one core per cavity. In this configuration, the cylindrical cavity 122 has an opening 126 with a diameter slightly larger than that of the lithium ion core member 102. Opening 126 faces and is exposed to a shared atmosphere region 128 within enclosure 116. The walls of the cylindrical cavities 122 are advantageously made to prevent electrolyte communication between adjacent cavities. Thus, the walls of the cavities 122 serve to enclose the electrochemical cells/jelly rolls located therein and prevent fluid flow from any individual cavity to any adjacent cavity.

The anode/cathode of the core member is also directly exposed to the common ambient area 128 without a single smaller enclosure (e.g., a metal container or polymeric bag that provides a hermetic seal between the moving core members). Eliminating the need for a metal container to package the core member not only reduces manufacturing costs, but also improves safety. In the event of a failure of the core component and a fire, the vented gases can occupy a common environmental area 128 that is much larger than the volume provided by a typical individual "metal container package" core component. In the event that the core member of the metal container package increases in pressure, an explosion is more likely to occur than in the present disclosure, which provides a greater volume for gas to occupy and thus reduces the increase in pressure. In addition, metal containers typically rupture at much higher pressures than the structures of the present disclosure, resulting in the mild failure modes of the present disclosure.

Within each cavity 122 is placed a thin cavity liner 124, which is located between the support member 120 and the lithium ion core members 102 a-i. Typically, all of the cavity liners (10 in this case, corresponding to the number of cavities) are formed as part of a monolithic cavity liner member 124'. The liner is preferably made of polypropylene, polyethylene or any other plastic that is chemically inert to the electrolyte. The liner may also be made of ceramic or metallic materials, although these are costly and not preferred. However, in the case of the support member being electrically conductive, the liner must be electrically insulating to electrically isolate the core member from the support member. Cavity liners are important for a variety of reasons. First, they are impermeable to moisture and electrolytes. Secondly, they may contain flame retardants capable of extinguishing flames, and thirdly, they allow easy-to-seal plastics materials to contain the electrolyte in a gas-tight seal.

During manufacturing, the electrolyte may be simultaneously filled into the cavity 122 in a subsequent manufacturing process, and then simultaneously subjected to molding and capacity grading processes. The forming process involves charging the cell to a constant voltage (typically 4.2V) and then allowing the cell to stand at this potential for 12 to 48 hours. Capacity grading occurs during the charge/discharge process, where the battery is fully discharged to a lower voltage (e.g., 2.5V), then charged to a maximum voltage (typically in the range of 4.2 to 4.5V), and then discharged again, where the capacity is recorded. Due to the inefficiency of the charging/discharging process, multiple charging/discharging cycles may be required to obtain accurate capacity grading.

Since the cavity liner is in close fit with the core, the cavity liner is able to introduce a precise and constant amount of electrolyte into each core member. One way to accomplish this is to provide a through hole in the housing 116, which can then be filled and sealed after the electrolyte is introduced into the cavity and processed. A core member having a capacity of about 3Ah will require about 4 to 8 grams of electrolyte depending on the density and surrounding porous material. Electrolyte filling is performed so that the entire jellyroll is uniformly wetted, not allowing for dry areas. Preferably, each core member has an equivalent weight of electrolyte from core to core that varies by within 0.5g, more preferably within 0.1g, even more preferably within 0.05 g. This variation is adjusted with the total amount of electrolyte and is typically less than 5%, even more preferably < 1%, of the total amount of electrolyte per core. Placing the assembly in a vacuum helps to perform this filling process and is critical for complete and uniform wetting of the electrodes.

The size, spacing, shape, and number of cavities 122 in support member 120 may be adjusted and optimized to achieve the desired operating characteristics of the battery while still achieving the safety features described above, such as mitigating fault propagation between/among core members 102.

As shown in FIG. 2, support members 220a-h may have different numbers of cavities, preferably in the range of 7 to 11, and have different configurations, including support members having cavities of different sizes, as is the case with support members 220d and 220 h. The number of cavities is always greater than 2 and is not particularly limited at the upper end except for the geometry of the support member and the core size. The actual number of cavities is typically between 2 and 30. The cavities may be evenly distributed, as in support member 220f, or they may be staggered, as in support member 220 g. The cavity diameter and the diameter of the core member that may be inserted into the cavity of each support member 220a-h as shown are also shown in fig. 2, and in addition, the capacity in ampere-hours (Ah) for each configuration is also shown.

Different shapes of the cavity and core member may also be used. As shown in fig. 3, the support member 320 includes a cavity 322 having a rectangular shape for receiving a similarly shaped core member 302. In fig. 4, the support member 420 has a mixture of rectangular cavities 422 and cylindrical cavities 402 for receiving a similarly shaped core member (not shown).

In an exemplary embodiment, when the MC battery has only core members arranged in parallel, the core members may include one or more core members optimized for power and one or more core members optimized for energy. In another particular case, the anodes or cathodes of some core members of the MC battery use certain materials, while the anodes and cathodes of other core members use different materials. In yet another particular case, the anode or the cathode may have electrodes of different thicknesses. Any combination of electrode thickness, cathode or anode active material or electrode formulation with variation can be combined in parallel strings in order to meet the energy/power ratio of the cell. Some core members may be configured to withstand rapid power pulses, while other core members may be optimized for high energy storage, thereby providing a battery capable of handling high power pulses while having a high energy content. However, it is important that the core member has a chemistry matched to the electrochemistry in order to provide chemical stability to the selected chemistry within the voltage window.

For example, LiCoO₂The cathode may be reacted with LiNi_0.8Co_0.15Al_0.05O₂Cathode matching, as long as a high potential of 4.2V is used, and a low potential of about 2V to 2.5V, however, when the potential exceeds 4.2V, for example, 4.3V is reached, for example, magnesium-doped LiCoO₂The material should not be matched to the NCA material because NCA materials degrade at higher voltages. However, in the latter example, the two materials may be mixed as long as the high potential is limited to 4.2V. The purpose of the present disclosure is to use mixed cathode materials in the correct voltage range and the inventors have found a particularly useful combination for high energy or high power, as will be explained in detail in the following description.

Power and energy optimization can be done by adjusting the electrode formulation (e.g., using higher levels of conductive additives to increase conductivity) or by using electrodes of different thicknesses. Additionally, the energy core may have one set of active materials (cathode and anode) while the power core may have another material. When using this method, it is preferred that the materials have a matching voltage range, for example 2.5 to 4.2V, or in the case of a high voltage combination 2.5 to 4.5V, to avoid decomposition. The high voltage is characterized by 4.2V and is typically below 5V for each isolated core member in a lithium-ion multi-core battery.

Prismatic core member

In fig. 5, an exemplary shape of a core member 502a suitable for use in the present disclosure is shown. This is a jellyroll structure, but has a prismatic shape rather than a cylindrical or rectangular shape as previously described. The core member includes an anode 530a, a cathode 532a, and an electrically insulating separator 534 a. Although not shown in the previous figures, each core member includes a separator between the anode and the cathode. The core member 502b is also prismatic, but a stacked structure including an anode 530b, a cathode 532b, and a separator 534b is used.

Connected in series

So far, core members electrically connected in parallel have been shown, but they may be connected in series or in a combination of parallel and series. As shown in fig. 6, there is a support member 620 (made of aluminum foam or polymer foam) with an inserted core member 602. For clarity, the tab connecting the core member to the bus bar is not shown, but is present. The negative battery terminal connector 640 is electrically connected to the low voltage bus bar 642. The positive battery terminal connector 644 is electrically connected to the high voltage bus bar 646. Adjacent block buss bars 648 and 650 connect each core member in their respective rows in parallel. Each bus bar 642, 644, 648 and 650 has a complementary bus bar on the opposite side of the core member, which bus bar is not shown. Each parallel bus is connected in series by three connecting lines 652, respectively, forming a series electrical path. Sense cables 654a-654e are located at each unique electrical point to allow detection of the voltage level at each parallel-linked core voltage point in the series system. These wires may also be used to provide a balancing current to maintain the core member in the same state of charge during charging and discharging and to connect to the feed through contacts 656. One skilled in the art of battery balancing systems will appreciate the purpose of such connection in the cells of the present disclosure having series-connected cores.

Fig. 6B shows a housing 616 that houses the support member 320. The housing 616 includes a plastic cover 658 and a box 660 hermetically sealed by ultrasonic welding. At the end of the housing 616 opposite the side of the lid 658 is a feedthrough sense contact 656. Extending from the cover 658 are a negative battery terminal connector 640 and a positive battery terminal connector 644. It will be appreciated that a person skilled in the art may implement various arrangements regarding the position of the connector sensing contacts, and that different series or parallel arranged batteries may also be used for the purposes of this disclosure.

In the case of a metal lid, it is closed by a welding method such as laser welding, in the case of a plastic lid, an adhesive (glue) may be used, or a thermal or ultrasonic welding method or any combination thereof may be used. This provides a properly sealed MC battery. The cores are connected in parallel or in series within the housing.

All feedthroughs, sensing, power, pressure, etc. need to be hermetically sealed. The hermetic seal should withstand an internal pressure in excess of or equal to about 1 atmosphere and should also withstand a vacuum, preferably greater than 1.2 atmospheres. The vent may also be provided on the container, the internal pressure of which should be below the pressure allowed by the seal.

Another way to provide balancing and sensing capability is to have a separate connector that provides external leads from each of the positive and negative terminals of the separate core members, allowing a connector external to the vessel to be connected with each of the separate core members. The balancing circuit detects an imbalance in the voltage or state of charge of the series connected cells and provides a passive or active balancing method known to those skilled in the art. The connecting leads are separate from the terminals that conduct current from the cells to provide power from the battery, and these terminals are used only when the cells are connected in series within the container. The sense leads may be selectively fused to the exterior of the container to prevent current flow through the respective jelly cores via the sensing circuitry.

Common wall compartmentalization

In an exemplary embodiment, as shown in fig. 7, the module 700 includes a divided enclosure 702, the divided enclosure 702 further including a plurality of support members 704, e.g., a different support member 704 located in each divided region 705. As described above, it is the support member 704 that houses the lithium ion core member 102, for example, an open winding core having a substantially cylindrical shape. In the exemplary embodiment of fig. 7, the lithium ion core members are arranged in a series of rows staggered with respect to adjacent rows to increase the density of electrochemical cell deployment. Various shapes and sizes of lithium ion core members may be used in conjunction with the present disclosure, and certain shapes and sizes are described throughout the present disclosure. It is noted that the above teachings are incorporated into this sub-title unless otherwise indicated. In this configuration, all the lithium ion core members 102 are connected in parallel, but it is apparent to those skilled in the art that they may be connected in series or in other configurations.

In one embodiment, the housing 702 includes a set of conductive tabs (not shown) connected to the cathode of each core member 102 and a set of conductive tabs (not shown) connected to the anode of each core member 102. A tab (not shown) is also connected to the cathode bus bar (not shown), and a tab (not shown) is connected to the anode bus bar (not shown). The cathode tab (not shown) and the anode tab (not shown) are welded to the bus bar (not shown) using spot welding or laser welding techniques. Bus bars (not shown) are interconnected to a positive terminal (not shown) and a negative terminal (not shown), respectively, outside of the module housing 702.

In another embodiment, included within the housing 702 is a first bus bar (not shown) that interconnects the anode of the core member to the positive terminal member of the terminal located outside of the housing, and a second bus bar (not shown) that interconnects the cathode of the core member to the negative terminal member of the terminal located outside of the housing 702. The bus bar may be used in a pressure-break configuration, as will be described in more detail below. The first and second busbars may be made of any electrically conductive material, in particular aluminium and/or copper.

The support member 704, which may be manufactured as part of the housing 702 or as a separate part, defines a cavity that is configured and dimensioned such that the lithium-ion core member 102 located therein has sufficient space so that limited expansion may occur during charge and discharge reactions, thereby preventing mechanical interaction of the respective lithium-ion core members during typical charge/discharge operations. Preferably, the support member 704 is made of plastic or ceramic material, but it is also conceivable to be made (entirely or partially) of metal. The housing 702 may also be made of various materials, such as plastic, ceramic, metal, and combinations thereof. If metal is used, bare steel is not preferred, and it is often advantageous to coat the metal (e.g., steel) housing 702 with an inert metal such as nickel. Preferred metals are aluminum, nickel or other metals that are inert to the chemicals used. Various plastics and ceramics may be used, provided that they are inert to the chemical and electrochemical environment. Examples of plastics and ceramics are polypropylene, polyethylene, alumina, zirconia. The housing 702 may also include a flame retardant mesh attached to the exterior of the housing in order to prevent a fire from reaching the interior of the housing.

In one embodiment, a cover (not shown) may be secured to the housing 702 to form a hermetically sealed system. The cover may be secured to the housing 702 using conventional manufacturing techniques. In the case of a metal component, a welding method, such as laser welding, may be used to secure the cover relative to the housing 702. In case of plastic, an adhesive (glue) may be used, or a thermal or ultrasonic welding method or any combination thereof may be used.

In another embodiment, the first plate and the sidewall are bonded using conventional manufacturing techniques to form the housing 702. In the case of a metal component, the housing 702 may be formed using a welding method such as laser welding. In case of plastic, an adhesive (glue) may be used, or a thermal or ultrasonic welding method or any combination thereof may be used. Once the operative elements are positioned within the housing 702, a second plate (or cover) may be secured thereto to define a hermetically sealed system.

In the exemplary embodiment shown in fig. 7, the housing 702 also includes six (6) distinct partitioned areas 705 containing six distinct support members 704 therein. The separation regions 705 (i.e., separation regions 705(a) -705(F)) are separated by common walls 706 (i.e., common walls 706(a) -706 (e)). The common wall 706 may be made of the same or similar material used in making the housing 702. Further, the common wall 706 may be made as an integral part of the housing 702 (e.g., integral with the bottom or side walls of the housing 702) or may be manufactured as a separate component attached to the housing 702 using the manufacturing techniques described above. Further, the common wall may define a portion of the wall or may define the entire wall. For the partially common wall 706, the enclosure 702 will define a shared atmosphere across and between adjacent partitioned regions; however, for the entire common wall 706 (i.e., the common wall extending from the bottom of the battery system to the top/cover of the battery system), each partition region will have a separate/different (i.e., unshared) atmosphere region. In implementations where the electrochemical cells are deployed in series connection, it may be advantageous to completely isolate each of the separation regions 705 with the entire common wall 706, for example to prevent the first shared atmosphere region from communicating with the second shared atmosphere region (and similar isolation between all adjacent separation regions by the entire common wall).

Because the housing 702 has continuous surfaces (e.g., top plate, bottom plate, side walls) in direct communication with each of the partitioned areas 705, heat sink plates or heat sink elements may be in contact with and/or attached relative to the continuous surfaces (e.g., top plate, bottom plate, side walls) of the housing 702 to facilitate heat dissipation of the electrochemical cells 102 located in the housing. The inclusion of a heat spreader plate/heat spreading element may eliminate the need for other heat spreading features (e.g., spaced apart heat spreading loops interleaved between cells), thereby saving cost over some conventional systems. In another embodiment, individual heat spreaders/heat dissipating elements may be positioned within each separation region 705, and the characteristics/geometry of individual heat spreaders/heat dissipating elements may vary from separation region to separation region, e.g., based on the design and operation of the electrochemical cells positioned within such separation region 705.

The incorporation of separate partitioning regions 705 into one housing 702 allows for more efficient and cost effective packaging using conventional packaging techniques involving separate battery modules, and the ability to accommodate more lithium ion core components within a comparable volume. For example, reference is made to the exemplary embodiment of fig. 7, which schematically illustrates six different separation regions 705. In conventional battery systems, each of the separation regions will take the form of an individual battery module. In conventional systems, when two modules are placed side by side, the outer wall of a first battery module will be in physical contact with the outer wall of an opposing second battery module. In the advantageous battery system shown in fig. 7, five walls are effectively eliminated because a single common wall 706 is located between adjacent divided regions 705 (rather than side-by-side outer walls). In this manner, additional "footprint" is provided for the electrochemical cells that generate energy when compared to similar overall shape dimensions. Furthermore, eliminating separate housings and the use of a common wall between adjacent partitioned areas reduces costs by eliminating additional and/or redundant materials. The multi-compartment area of the exemplary housing 702 is easily scalable and may vary in size to meet the desired size and power output of a particular customer and/or application. It is worth noting that according to the exemplary method shown in fig. 7, the number of separation regions is always at least two (i.e., there is at least one common wall 706), but scalable to significantly larger sizes, as will be apparent to those skilled in the art.

As described above, in the exemplary embodiment of FIG. 7, housing 702 includes six partitioned areas 705A-F and five common walls 706 a-e. Within each cell 705 is a support member 704, the support member 704 configured to maximize the number of ionic core members 102 contained therein; referring to fig. 2, an exemplary ion core member 102 cavity configuration, for example. In the illustrative embodiment, the support member 704 includes 78 ion core members 102 housed in an off-center/staggered configuration in each partitioned region. Accordingly, 468 ion core members 102 are contained within six evenly distributed divided regions 705 of the housing 702.

Furthermore, in implementations where the core members 102 are electrically connected in parallel, the enclosure 702 safely supports a shared atmosphere across and between the partitioned areas, at least in part because the vapor pressure generated by the "open" jellyroll is lower than the corresponding pressure in a system where the core members 102 are connected in series. As described above, when the common wall 706 between adjacent divided regions extends only over a portion of the distance from the bottom plate to the top plate/cover of the housing 702, a shared atmosphere is provided between and among the adjacent divided regions 705. Because there is a space between the partially common wall and the boundary/outer wall of the housing 702, the associated separation regions are not hermetically sealed with respect to one another. The shared atmosphere allows vapor communication (and shared pressure build-up) across and between each of the divided regions 705. In the event of a core component instability and/or failure, the gas vented from the core component can occupy a shared atmosphere area, which provides a larger volume to accommodate such gas/pressure buildup (and shared venting/pressure disconnect function) than conventional modular battery systems.

A cavity liner may be placed/positioned within each cavity of the support member 704, and the lithium ion core member 102 may be positioned within the liner. All of the cavity liners (e.g., in the exemplary embodiment shown in fig. 7, there are seventy-eight (78) cavity liners, which correspond to the number of cavity/li-ion core members in each partitioned region) may be formed as part of a monolithic cavity liner member, or they may be formed separately. The chamber liner is typically made of polypropylene, polyethylene, or any other plastic that is chemically inert to the electrolyte. The liner may also be made of a ceramic or metallic material. However, where the support member is electrically conductive, the cavity liner is typically electrically insulating to electrically isolate the lithium ion core member from the support member. The disclosed cavity liners can serve several beneficial functions, for example, the cavity liners can (i) be impermeable to moisture and electrolyte, (ii) can contain flame retardants capable of extinguishing flames, and/or (iii) facilitate maintaining the electrolyte associated with each lithium ion core member in a hermetic seal.

During manufacturing, the electrolyte may be simultaneously filled into the cavity of the support member in a subsequent manufacturing process, and then simultaneously subjected to molding and capacity grading processes. The forming process involves charging the cell to a constant voltage (e.g. 4.2V) and then allowing the cell to stand at that potential for a period of time, for example 12 to 48 hours. Capacity grading typically occurs during charge/discharge, where the battery is fully discharged to a lower voltage (e.g., 2.5V), then charged to a higher voltage (typically in the range of 4.2 to 4.5V), and then discharged again, where capacity is recorded. Multiple charge/discharge cycles are required or used to obtain accurate capacity grading.

The disclosed cavity liner is capable of introducing a precise and constant amount of electrolyte to each core member due to the close fit with the core. One way to accomplish this is to provide a via in the housing 702, which can then be filled and sealed after the electrolyte is introduced into the cavity. A core member having a capacity of about 3Ah may require about 4 to 8 grams of electrolyte depending on the density and surrounding porous material. Electrolyte filling is typically performed so that the entire jellyroll is uniformly wetted, not allowing for dry areas.

The size, spacing, shape, and number of cavities in support member 704 may be adjusted and optimized to achieve the desired operating characteristics of the battery while still achieving the "packing density" and safety features described above, such as mitigating fault propagation between/among core members 102.

Further, in a shared atmosphere enclosure, at least one pressure cutoff device/feature may be integrated inside and/or on the surface of enclosure 702. The pressure disconnect device/feature may be of the type disclosed in U.S. non-provisional patent application serial No. 15/562,792, assigned to onneured et al. The contents of the above application are incorporated herein by reference. The pressure threshold can be greater than 5psig, such as 5psig to 40psig, as described below.

In an exemplary embodiment, a pressure disconnect device ("PDD") advantageously electrically isolates the electrochemical cells 102 associated with the lithium ion battery in response to a pressure buildup within the housing 702 exceeding a predetermined pressure threshold. The PDD includes a deflectable dome structure and a fuse assembly positioned on an outer surface of the housing 702 that is adapted to electrically isolate a lithium ion battery assembly within the housing 702 in response to a pressure buildup within the housing 702 exceeding a threshold pressure level. Associated with the fuse assembly is a structural feature aligned with the centerline of the deflectable dome.

When the internal pressure reaches the PDD threshold, the flexible dome springs out to contact the structural features, causing a short circuit between the positive and negative terminals, resulting in a fuse failure. After the fuse fails (i.e., "blows"), the negative terminal connected to the external circuit is isolated from the jelly roll in the can and remains connected to the positive terminal through the housing 702 and structural features, thereby allowing current to flow directly from the negative terminal to the housing 702, i.e., bypassing the jelly roll 102.

In another exemplary embodiment, the overcharge shutdown device advantageously electrically isolates the electrochemical cells 102 associated with the lithium ion battery in response to the pressure buildup within the housing 702 exceeding a predetermined pressure threshold. The overcharge trip unit utilizes the known characteristics of the housing 702 (i.e., the expansion of the battery case in response to an increase in internal pressure) to disconnect the electrochemical cell 102 from the housing 702. A provisional patent application entitled "overcharge power-off device" filed concurrently by the applicant discloses exemplary embodiments thereof and is incorporated herein by reference.

As described above, the housing 702 may include bus bars in electrical contact with the electrochemical cells 102 and in electrical contact with a flexible surface (e.g., a flexible backplane) of the housing 702. As the internal pressure of the housing 702 increases, the likelihood of the housing 702 expanding and deforming will also increase. The top and bottom plates have the greatest surface area and therefore generally have the greatest expansion/bulging potential compared to the side walls. Resistance welds connecting the bus bars to the base plate are subject to stress when a force is applied to the base plate due to an increase in internal pressure, and eventually cause the resistance welds to break/pop out, thereby forming a gap between the bus bars and the base plate. This gap electrically disconnects the winding core from the base plate of the housing 702.

As described above, within each of the partitioned areas 705 (i.e., areas 705A-705F) is an electrically insulating support member 704, which may be made of ceramic, plastic (e.g., polypropylene, polyethylene), or other material (e.g., aluminum foam). The support member 704 may be sufficiently deformable/compressible to protect the core member 102 from damage in/if an impact occurs. In addition, the thermal conductivity needs to be made application-friendly by: that is, heat is dissipated during battery charging and discharging, thereby generating a uniform temperature distribution; and heat dissipation during catastrophic failure (e.g., internal short circuit causing thermal runaway of one core member). Proper heat dissipation characteristics can limit the chance of a cascade between cores going out of control. The support member 704 may also absorb electrolyte, which may be trapped in the support member 704 if discharged during abuse of the core member 102.

A support member 704 that is deformable and can absorb kinetic energy is particularly desirable because it distributes the impact load over a larger area, thereby reducing the amount of local deformation at each core member 102, reducing the likelihood of electrical shorting. Examples of kinetic energy absorbing materials are foams (e.g., aluminum foam, plastic foam), porous ceramic structures, honeycomb or other open structures, fiber filled resins, and phenolic materials. Examples of fibrous fillers for plastics and resin materials may be glass fibres or carbon fibres.Examples of aluminum-containing energy absorbers are aluminum foams having open or closed cells, aluminum honeycomb structures, and engineered materials (e.g., Altucore)^TMAnd CrashLite^TMMaterial). When the support member collapses during impact, collision or other mechanical abuse, it is important to protect the core from being punctured as much as possible to avoid internal mechanical shorts. This will create a more secure structure. Further discussion regarding energy absorbers is disclosed above, and further described with reference to FIG. 1C.

The support member 704 may be sufficiently deformable/compressible to protect the core member 102 from damage in/if an impact occurs. In addition, the thermal conductivity needs to be made application-friendly by: that is, heat is dissipated during battery charging and discharging, thereby generating a uniform temperature distribution; and heat dissipation during catastrophic failure (e.g., internal short circuit causing thermal runaway of one core member). Proper heat dissipation characteristics can limit the chance of a cascade between cores going out of control. The support member 704 may also absorb electrolyte, which may be trapped in the support member 704 if discharged during abuse of the core member 102.

A support member 704 that is deformable and can absorb kinetic energy is particularly desirable because it distributes the impact load over a larger area, thereby reducing the amount of local deformation at each core member 102, reducing the likelihood of electrical shorting. Examples of kinetic energy absorbing materials are foams (e.g., aluminum foam, plastic foam), porous ceramic structures, honeycomb or other open structures, fiber filled resins, and phenolic materials. Examples of fibrous fillers for plastics and resin materials may be glass fibres or carbon fibres. Examples of aluminum-containing energy absorbers are aluminum foams having open or closed cells, aluminum honeycomb structures, and engineered materials (e.g., Altucore)^TMAnd CrashLite^TMMaterial). When the support member collapses during impact, collision or other mechanical abuse, it is important to protect the core from being punctured as much as possible to avoid internal mechanical shorts. This will create a more secure structure. Further discussion regarding energy absorbers is disclosed above, and further described with reference to FIG. 1C.

Structure for controlling gas/fluid flow from an electrochemical cell

In an exemplary embodiment, the housing 116, 616, 702 may include structure for controlling gas/fluid flow from the electrochemical cells located therein. In an exemplary embodiment and as shown in fig. 8, the disclosed structure for controlling gas/fluid flow can take the form of a blanket or mat 804, which mat or mat 804 is positioned in contact with (or in close proximity to) jellyroll assembly 102 (particularly the open end of jellyroll assembly 102) contained within a support member. The blanket 804 substantially limits the amount of hot particulate residue (e.g., liquid electrolyte and electrolyte gases) from interacting with adjacent jellyroll 102 if/when released from one or more jellyrolls. In an exemplary embodiment, the blanket 804 includes holes/features that facilitate electrolyte charging and electrical connection between the electrochemical cells and associated bus bars.

The blanket 804 generally has flow characteristics that promote axial gas and fluid flow through the blanket 804, but substantially reduce lateral (e.g., side-to-side) flow within the blanket 804. As a result, particles associated with such gas/fluid flow are forced through the body of the blanket 804 and into the shared atmosphere (or individual separation regions 707) of the housing 116, 616, 702. Within the range of the applicable threshold pressure being reached in the shared atmosphere, the gas/liquid containing particles are discharged from the enclosure.

In one illustrative embodiment, the blanket 804 is made of a ceramic material (or the like) with apertures/structures to facilitate axial flow thereof. Ceramic materials are generally stable at higher temperatures, for example greater than 200 ℃. In exemplary embodiments of the present disclosure, the pore size of the disclosed blanket is sized to (i) capture larger hot particles/debris, such as larger sized carbonized, metal oxide, and molten metal particles, to ensure that those larger particles/debris do not contact the adjacent jellyroll 102, and (ii) pass smaller particles and gas through the blanket 804 and out of the vent holes (if the vent holes are activated). For the purposes of this disclosure, smaller particles are those that will pass freely through the vent so as not to be trapped/blocked within the vent outlet. In one exemplary embodiment, the carpet 804 is mounted below the bus bar 806; however, the carpet 804 may be mounted over the bus bar 806.

Although the disclosed structure for controlling gas/fluid flow from an electrochemical cell is described/depicted as a blanket 804, it should be noted that the desired function of controlling gas/fluid flow may be achieved by a plurality of discrete elements located in proximity to the electrochemical cell, for example, in a one-to-one manner. Thus, each gas/fluid flow element may be positioned proximate the open end of each jellyroll, as described above with reference to the blanket 804, to promote axial/non-lateral flow of gas/fluid exiting the jellyroll while capturing larger particles. In a similar manner, the disclosed structures for controlling gas/fluid flow may be configured/sized to provide fluidic functionality with respect to a subset of electrochemical cells (e.g., rows or columns of electrochemical cells) located within the housing.

Embodiments of the housing

In another exemplary embodiment of the present disclosure, referring to fig. 9A, the housing 116, 616, 702 may be configured with an egg-shaped box wall 900 such that upon mechanical impact of the housing, the MC battery may short circuit outside the housing. The egg-box shaped portion 902 of the wall 900 made of aluminium is in contact (before impact) with a sheet 904 of non-conductive material made of polyethylene plastic. A second plate 906 made of aluminum or other conductive material is located below the plastic plate 904. The egg-shaped box material 902 is connected to the negative or positive pole of the MC battery, while the other conductive plate 906 is connected to the opposite pole. When an impact, nail penetration, or abnormal pressure is applied to the walls, such as in a crash, the egg-shaped walls 902 compress, causing the plastic plate 904 to be penetrated and make contact with the conductive plate 906 external contact points 908a-d, as shown in fig. 9B, creating an external electrical short in the MC battery.

As described above, the respective core members are generally connected by the internal bus bars. Sometimes, the bus bar common connector may be a wire or a plastic coated wire. It may also be a solid metal such as copper, aluminum or nickel. The bus bars connect multiple core members in series or in parallel and have the ability to divert current in the multi-core member structure to the connectors, thereby allowing external connection to the multi-core array. In the case of external bus bars, each winding core needs to be individually threaded through the connector by the housing.

Whether internal or external bus bars are used, they may be configured to provide a fuse between the core members. This can be achieved in a number of ways, including forming the bus bar with a cross-section that is limited to an area that can only carry a certain current, or by limiting the size of the lugs that connect the core member to the bus bar. The bus bar or lug may be constructed as a one-piece stamping or other metal forming technique, or by using a second portion that connects portions of the bus bar to the fuse device. For example, if two rectangular cross-sectional areas of copper bus bars are used, in which the anode and cathode tabs of 10 core members are connected to each other by the bus bars, the cross-sectional area of each bus bar is 10mm²At least one region on the bus bar can be fabricated with a reduced surface area compared to the remainder of the bus bar. This provides a location where fusing occurs and current carrying capability is limited. The fuse area may be at one or more points of the bus bar, preferably between each core member, but is most effective with multiple cells at the midpoint. This fuse will limit the heat generation of the core member if an external short circuit occurs, and it is possible to avoid thermal runaway. Also, in the event of an internal short circuit in the core member, whether due to a manufacturing defect or due to an external penetration in the event of abuse, such as a nail penetrating into the core member, causing an internal short circuit in the battery, such a fuse arrangement can limit the amount of current flowing to the internal short circuit by isolating the failed core from the other parallel cores.

The empty space inside the outer shell may be filled with a shock absorbing material, such as foam or other structures having less influence on the core member, thereby further reducing the risk of internal short circuits. Such reinforcement may also provide a means of transferring the natural frequency of vibration of the internal contents to the housing, thereby improving resistance to shock and vibration and mechanical life. The filler material should preferably contain a flame retardant material that will extinguish any fire that may occur during a thermal runaway of the battery or melt during the same thermal runaway, thereby absorbing excess heat and limiting heating of the battery. This provides greater security in the event of a catastrophic event.

Examples of flame retardant materials can be found in published engineering literature and manuals, such as polyurethane Handbook published by Hanser Gardner Publications or those described in US 5198473. In addition to polyurethane foam, epoxy foam or glass fiber wool and similar non-chemically or electrochemically active materials can also be used as filling material for the empty areas inside the housing. In particular, hollow or dense spheres or irregularly shaped particles made of plastic, metal or ceramic can be used as low-cost fillers, in the case of hollow spheres, which would provide an additional energy absorption means in the event of a collision of the multicore battery. In a particular case, the support member is foamed aluminium. In another particular case, the support member is a dense aluminum foam having an aluminum density of 10-25%. In yet another particular case, the cells in the aluminum foam have an average diameter of less than 1 mm.

The housing 116, 616, 702 may also be configured as a flip-top configuration, wherein symmetrically identical sidewall members are attached together along a pair of seams to define the housing 116, 616, 702. In an exemplary embodiment, the sidewall components are attached along a vertical seam located at the center of the housing 116, 616, 702. In another exemplary embodiment, the flip cover configuration is attached along a horizontal seam located at the center of the housing 116, 616, 702. In yet another exemplary embodiment, the flip cover configuration is attached along an angled seam that symmetrically divides the housing 116, 616, 702. In yet another exemplary embodiment, the exterior of both sidewall members are the same, but the interior base of one or both sidewall members includes a partial or full partition wall, such as a shared wall, for forming separate partitioned areas within the housing 702. The flip-top configuration will be discussed below with reference to fig. 10-12.

In another exemplary embodiment, and referring to fig. 10A and 10B, flip assembly 1000 includes at least two side wall members 1002. Although referred to as two separate side wall members 1002A and 1002B, the side wall members 1002A, 1002B may be substantially similar (or identical) in shape. For this embodiment, side wall members 1002A and 1002B are referenced separately for illustrative purposes. Since like components/features have like reference numerals, no reference numeral of "a" or "B" refers to both side wall components 1002A and 1002B unless otherwise noted.

Fig. 10B depicts an exploded view of the flip assembly 1000, the flip assembly 1000 including at least two sidewall members 1002A, 1002B and a plate 1020. The side wall members 1002A, 1002B include a first side 1004, a second side 1006, and a third side 1008, as well as a first edge 1010 and a second edge 1012. The first edge 1010 and the second edge 1012 define edges of the sidewall member 1002 that can interface with the plate 1020. The first side 1004, the second side 1006 and the third side 1008 define a surface of one sidewall member 1002. In an exemplary embodiment, where only two sidewall members 1002 are required, each sidewall member may define half of a sidewall of flip member 1000.

In the illustrative embodiment, the second side 1006 and the third side 1008 are mounted perpendicularly in a direct or indirect relationship to the first side 1004. In such embodiments, the first side 1004 is longer than the second side 1006 and the third side 1008, and the second side 1006 is longer than the third side 1008. However, it will be apparent from the additional exemplary embodiments discussed below that the length suggestions for the first side 1004, the second side 1006, and the third side 1008 are merely exemplary and may be varied without departing from the spirit/scope of the present disclosure. The angle formed by the first and second sides 1004, 1006 and the first and third sides 1004, 1008 may further include an arcuate feature 1009. The arcuate feature 1009 may facilitate better utilization of the enclosure to achieve maximum core roll (not shown) packaging. The side wall members 1002A, 1002B may further include cutouts for various accessories, such as a PDD device and/or an exhaust/flame arrestor. The cutouts may be located on the sidewall assemblies 1002A, 1002B and/or the plate 1020. Although depicted as one plate 1020, additional plates may be used opposite plate 1020.

In an exemplary embodiment, where the shape of the sidewall members 1002A, 1002B are substantially similar, the manufacture of the flip assembly 1000 includes aligning the sidewall members 1002A, 1002B such that when the surfaces 1014A and 1016B and 1014B and 1016A are in contact, the desired flip shape (e.g., square, rectangular, circular, oval, etc.) is obtained. More specifically, assembling flip assembly 1000 includes aligning sidewall assemblies 1002A, 1002B such that second side 1006A and third side 1008B and second side 1006B and third side 1008A are aligned. Once attached, the surfaces 1014B and 1016A and 1014A and 1016B form a seam 1018 that helps form one seamless and flat sidewall of the flip assembly 1000. In the case of metallic sidewall components 1002A, 1002B, the manufacture of the seam 1018 may include a welding process, such as laser welding and/or an adhesive. In the case of plastic/ceramic sidewall members 1002A, 1002B, the fabrication of the seam 1018 may include adhesives and/or thermal or ultrasonic welding methods. Other fabrication techniques are discussed below. In this embodiment, the seam 1018A is not opposite the seam 1018B where the second side surface 1006 and the third surface 1008 have different lengths.

The assembly of the plate 1020 may be completed at any time during the assembly of the side wall members 1002A, 1002B. For example, as described above, the side wall members 1002A, 1002B can be manufactured together and the plate 1020 assembled to one or both of the surfaces 1010, 1012 when the side wall members 1002A, 1002B are assembled. However, in another example, the side wall member 1002 is assembled to the plate 1020 such that either side wall member 1002A or 1002B further includes the plate 1020. In the process of manufacturing the flip-type assembly 1000, the second sidewall member 1002 is attached to the plate 1020 and the surfaces 1014, 1016 of the first sidewall member. Another panel, not shown, can be placed on the opposite side of panel 1020 to complete flip assembly 1000 and form a hermetically sealed modular housing. The above-described flip-top configuration may further provide cost savings by substantially reducing manufacturing/assembly operations. For example, as disclosed herein, the disclosed flip cover components can be advantageously bonded around one or more pre-assembled support members containing electrochemical cells. Plate 1020 may further include features (e.g., grooves) that capture sidewall assembly 1002.

In another exemplary embodiment, and referring to fig. 11, the flip member 1050 includes at least two side wall members 1052. Although referred to as two separate side wall members 1052A and 1002B, the shape of the side wall members 1052A, 1052B may be substantially similar (or identical). For this embodiment, the side wall members 1052A and 1052B are referenced separately for illustrative purposes. Since like components/features have like reference numerals, reference numerals without an "a" or "B" refer to the two side wall members 1052A and 1052B unless otherwise noted.

Fig. 11 depicts an exploded view of the flip assembly 1050, the flip assembly 1000 comprising at least two side wall members 1052A, 1052B and a plate 1064. The side wall members 1052A, 1052B include a first side 1054, a second side 1056, and a first edge 1058 and a second edge 1060. The first edge 1058 and the second edge 1060 define edges of the side wall member 1052 that can interface with the plate 1064. The first side 1054 and the second side 1056 define a surface of one side wall member 1052. In an exemplary embodiment, where only two sidewall members 1052 are required, each sidewall member may define half of the sidewalls of the flip member 1050.

In an exemplary embodiment, the second side 1056 is mounted vertically in a direct or indirect relationship to the first side 1054. In such embodiments, the first side 1054 is longer than the second side 1056. However, the length suggestions for the first side 1054 and the second side 1056 are merely exemplary and may be varied without departing from the spirit/scope of the present disclosure. The angle formed by the first side 1054 and the second side 1006 may further include a curved feature 1057. The curved feature 1057 may facilitate better utilization of the outer shell for maximum core roll (not shown) packaging. The side wall members 1052A, 1052B may further include cutouts for various accessories, such as PDD devices and/or exhaust/flame arrestors. The cutouts may be located on the side wall assemblies 1052A, 1052B and/or the plate 1064.

In the illustrative embodiment, because the shape of the side wall members 1052A, 1052B are substantially similar, the manufacture of the flip assembly 1050 includes aligning the side wall members 1052A, 1052B such that when the surfaces 1062A and 1062B of the second surface 1056 are in contact, a desired flip shape (e.g., square, rectangular, circular, oval, etc.) is obtained. Once attached, surfaces 1062A and 1062B form seams (not shown) to form one seamless and flat sidewall of flip assembly 1050. In the case of metallic side wall members 1052A, 1052B, the manufacture of the seam 1018 (not shown) may include welding methods, such as laser welding and/or adhesives. In the case of plastic/ceramic side wall members 1052A, 1052B, the manufacture of the seam 1018 (not shown) may include adhesives and/or thermal or ultrasonic welding methods. Other fabrication techniques are discussed below. In this embodiment, two seams (not shown) are opposite each other because the second side 1056 is always of uniform length.

The assembly of the plate 1064 may be accomplished at any time during the assembly of the side wall members 1052A, 1052B. For example, as described above, the side wall members 1052A, 1052B may be manufactured together and the plate 1064 assembled to one or both of the surfaces 1058, 1060 when assembling the side wall members 1052A, 1052B. However, in another example, the side wall member 1052 is assembled to the plate 1064 such that either of the side wall members 1052A or 1052B also includes the plate 1064. In the process of manufacturing the flip-type assembly 1050, the second side wall member 1052 is attached to the plate 1064 and the surface 1062 of the first side wall member. Another plate, not shown, can be placed opposite plate 1064 to complete flip assembly 1050 and form a hermetically sealed modular housing. The above-described flip-top configuration may further provide cost savings by substantially reducing manufacturing/assembly operations. For example, as disclosed herein, the disclosed flip cover components can be advantageously bonded around one or more pre-assembled support members containing electrochemical cells. The plate 1064 may further include features (e.g., grooves) that capture the sidewall assembly 1052.

In another exemplary embodiment, and with reference to fig. 12A-12C, the flip member 1100 includes at least two side wall members 1102. Although referred to as two separate sidewall members 1102A and 1102B, the sidewall members 1102A, 1102B may be substantially similar (or identical) in shape. For this embodiment, the side wall members 1102A and 1102B are referenced separately for illustrative purposes. Since like components/features have like reference numerals, reference numerals without an "a" or "B" refer to both side wall components 1102A and 1102B unless otherwise noted.

Fig. 12B and 12C depict exploded views of the flip assembly 1100, the flip assembly 1000 including at least two sidewall members 1102A, 1102B and a plate 1114. Fig. 12B and 12C show the flip member 1100 in alternate views. The side wall members 1102A, 1102B include a first side 1104, a second side 1106, and first and second edges 1108, 1110. The first edge 1108 and the second edge 1110 define the edges of the sidewall member 1102 that can interface with the plate 1114. The first side 1104 and the second side 1106 define a surface of one of the side wall members 1102. In an exemplary embodiment, where only two sidewall members 1102 are required, each sidewall member may define half of the sidewalls of the flip member 1100.

In the illustrative embodiment, the second side 1106 is mounted vertically in a direct or indirect relationship to the first side 1104. In this embodiment, the first side 1104 and the second side 1106 have substantially equal lengths. However, the length suggestions for the first side 1104 and the second side 1106 are merely exemplary and may be varied without departing from the spirit/scope of the present disclosure. In comparison to fig. 10 and 11, the side wall member 1102 encapsulates the plate 1114 from a narrower end 1116. The angle formed by the first side 1104 and the second side 1106 may further include a curved feature 1107. The curved feature 1107 may facilitate better utilization of the outer shell to achieve maximum core roll (not shown) packaging. The side wall members 1102A, 1102B may further include cutouts for various accessories, such as a PDD device and/or an exhaust/flame arrestor. The cutouts may be located on sidewall assemblies 1102A, 1102B and/or plate 1114. Although depicted as one plate 1114, additional plates may be used opposite the plate 1114. Fig. 12B and 12C show the plates 1114 on either side of the side wall member 1102 with the opposite plate 1114 removed for clarity.

In an exemplary embodiment, with the shape of the sidewall members 1102A, 1102B substantially similar, the manufacture of the flip assembly 1100 includes aligning the sidewall members 1102A, 1102B such that when the surfaces 1112A and 1112B of the second surface 1106 are in contact, a desired flip shape (e.g., square, rectangular, circular, oval, etc.) is obtained. Once attached, the surfaces 1112A and 1112B form a seam 1118 that helps to form one seamless and flat sidewall of the flip assembly 1100. In the case of metallic sidewall components 1102A, 1102B, the manufacture of the seam 1118 may include welding methods, such as laser welding and/or adhesives. In the case of plastic/ceramic sidewall components 1102A, 1102B, the fabrication of the seam 1118 may include adhesives and/or thermal or ultrasonic welding methods. Other fabrication techniques are discussed below. As discussed with reference to fig. 11, seam 1118A is opposite seam 1118B (not shown).

The assembly of the plate 1114 can be completed at any time during the assembly of the side wall members 1102A, 1102B. For example, as described above, the side wall members 1102A, 1102B may be manufactured together and the plate 1114 assembled to one or both of the surfaces 1108, 1110 when the side wall members 1102A, 1102B are assembled. However, in another example, the side wall member 1102 is assembled to the plate 1114 such that either of the side wall members 1102A or 1102B also includes the plate 1114. In the process of manufacturing the flip-type assembly 1100, the second side wall member 1102 is attached to the plate 1114 and the surface 1112 of the first side wall member. Another plate, not shown, can be placed opposite the plate 1114 to complete the flip assembly 1100 and form a hermetically sealed modular housing. The above-described flip-top configuration may further provide cost savings by substantially reducing manufacturing/assembly operations. For example, as disclosed herein, the disclosed flip cover components can be advantageously bonded around one or more pre-assembled support members containing electrochemical cells. Plate 1114 may further include features (e.g., grooves) that capture sidewall assembly 1102.

The side wall members 1002, 1052, 1102 and plates 1020, 1064, 1114 may be fabricated using a variety of materials (e.g., metals, plastics, ceramics). In the case of metals, it is preferred that at least the outermost surface is an inert material. For example, if the metal is not inert (e.g., steel), the components may be made of an inert metal or may be coated with an inert material. Such manufacturing and/or coating metals may include aluminum and nickel; however, other materials may be used, as described below. Furthermore, various plastics and ceramics can be used as manufacturing materials and/or as coating materials. Examples include polypropylene, polyethylene, alumina and zirconia. In addition, the side wall members 1002, 1052, 1102 and plates 1020, 1064, 1114 may be made of compressed paper.

The manufacture of the side wall members 1002, 1052, 1102 and panels 1020, 1064, 1114 may be accomplished by conventional manufacturing techniques (e.g., forming, machining, molding, extruding, and roll forming), wherein the manufacture of the members requires little secondary operations. However, the side wall members 1002, 1052, 1102 and panels 1020, 1064, 1114 may be assembled from at least two components using conventional attachment techniques (e.g., welding, adhesives, fasteners, bonding, crimping, and folding). In an exemplary embodiment, the side wall members 1002, 1052, 1102 are manufactured by shaping aluminum to create a second side (and a third side if desired) as discussed with reference to fig. 10-12. In another exemplary embodiment, some or all of the flip members may be made of compressed paper. Compressed paper can be made similar to other compressed materials (e.g., plywood and particle board) in that strips of paper are combined with a binder (e.g., sodium silicate) and compressed into a desired shape. The result is a flame retardant and moisture resistant part. In yet another embodiment, the non-flame retardant material may be coated with a material that prevents a fire from escaping from the inner housing and/or from entering the interior of the housing. In one example, a flame retardant mesh can be secured to the exterior of the flip member. However, fabrication is not limited to those techniques described above, and additional techniques will be apparent to those skilled in the art.

Anode

The anodes of these core members are those which are customary in lithium-ion or lithium-polymer batteries and are described in the literature, for example graphite, doped carbon, hard carbon, amorphous carbon, silicon (for example silicon nanoparticles or Si columns or carbon-containing dispersed silicon), tin alloys, Cu₆Sn₅Li, a metal foil substrate with Li deposited thereon, Si and Li, Li metal powder mixed in graphite, lithium titanate and any mixture thereof. Anode suppliers include, for example, Morgan Carbon, Hitachi Chemical, Nippon Carbon, BTR Energy, JFE Chemical, Shanshan, Taiwan Steel, Osaka Gas, Conoco, FMC Lithium, and Mitsubishi Chemical. The present disclosure is not limited to any particular anode compound.

Cathode electrode

The cathodes used in the jellyroll are standard cathodes in the industry, as well as some new high voltage mixtures, as will be described in more detail below. These new cathodes can be used in MC structures or single cells where the anode/cathode structure is contained in a sealed metal can or sealed polymer pouch. Due to the abundance of industrially available cathode materials, the material classes for each material group are referred to herein as "compounds"; each compound may have a range of compositions and be grouped according to crystal structure, chemical composition, voltage range applicability, or similarity of material composition and gradient changes. An example of a suitable variety of materials is Li_xCoO₂(referred to as Compound A), Li_xM_zCo_wO₂(compound B, wherein M is selected from Mg, Ti and Al, and partially substitutes Co or Li in the lattice, added in the range of Z ═ 0-5%, usually W close to 1, suitable for charging at 4.2V or more), Li_xNi_aMn_bCo_cO₂(especially about a ═ 1/3, b ═ 1/3, C ═ 1/3 (compound C) and a ═ 0.5, b ═ 0.3, C ═ 0.2 (compound D)), and Mg-substituted compounds thereof (both classified as compound E).

Another example is Li_xNi_dCo_eAl_fO₂(Compound F) and its magnesium-substituted derivative Li_xMg_yNi_dCo_eAl_fO₂(compound G) in particular cases d is 0.8, e is 0.15 and f is 0.05, but d, e and f can vary by a few percent and y ranges from 0 to 0.05. Another example of various cathode materials is Li_xFePO₄(Compound H), Li_xCoPO₄(Compound I) and Li_xMnPO₄(Compound J) and Li_xMn₂O₄(Compound K). In all of these compounds, an excess of lithium (X > 1) is generally found, but ranges for XThe enclosure may be between 0.9 and 1.1. One class of materials particularly suitable for high voltages (having high capacity when charged above 4.2V) are the so-called layered materials, described for example in US patent US7358009 by Thackeray et al, and commercially available from BASF and TODA (compound L).

The compounds described initially by Thackeray can remain stable at voltages above 4.2V. Some of these cathodes are stable at high voltages above 4.2V (the standard maximum voltage using graphite as the anode), and these materials may preferably be mixed. Although one of the above materials may be used in the present disclosure, it is preferable to mix two or more material compounds selected from B, C, D, E, F, G, I, J and L. In particular, mixtures of two or more compounds of compounds B, D, F, G and L are preferred. For very high energy density configurations, mixtures of (B and L) or (B and G) or (G and L) are most beneficial, and high power can also be achieved when they are made as thin electrodes. Thin (power) electrodes and thick (energy) electrodes may be entered into the core member to adjust the energy to power ratio while having the same suitable voltage range and chemistry.

A particular new cathode, the so-called core-shell gradient (CSG) material (called compound M), has a core with a different composition compared to its shell. For example, Ecopro ((website www.ecopro.co.kr or (http:// Ecopro. co. KR/xe/_0.8Co_0.iMn_0.i]O₂(1-x)Li[Ni_0.46Co_0.23Mn_0.31]O₂Referred to as "CSG material" (core-shell gradient), Y-K Sun also describes another M-type compound in electrochimica acta, Vol.55, No. 28, pp.8621-8627, and a third description of M-type compounds can be found in Nature Materials 8(2009), pp.320-324 (article by YK Sun et al), which describes a CSG material of similar composition but of the formula Bulk-Li (Ni)_0.8Co_0.1Mn_0.1O₂Gradient concentration of Li (Ni)_0.8-xCo_0.1+yMn_0.1+zWherein x is more than or equal to 0 and less than or equal to0.34, y is more than or equal to 0 and less than or equal to 0, l3, and z is more than or equal to 0 and less than or equal to 0.21; surface layer of Li (Ni)_0.46Co_0.23Mn_0.31)O₂. A fourth description can be found in patent WO2012/011785A2 ("785A 2" patent), which describes Li_x1[Ni_{1-y1-z1- w1}Co_y1Mn_zlM_wl]O₂(wherein, In the above formula, 0.9. ltoreq. x 1. ltoreq. l.3, 0. l. ltoreq. y 1. ltoreq.0.3, 0.0. ltoreq. z 1. ltoreq.0.3, 0. ltoreq. w 1. ltoreq.0.1, and M is at least one metal selected from the group consisting of Mg, Zn, Ca, Sr, Cu, Zr, P, Fe, Al, Ga, In, Cr, Ge and Sn). All four ranges of variants of compound M are incorporated herein as references for compound M used in various aspects of the present disclosure.

Preferably, the M compound may also have a Li content of about 1, but varying within a few percent, and the Li or Ni/Mn/Co compound may be substituted with Mg, Al and the first row transition metal, and one or more of these M compounds described above are preferably mixed with compound B, C, D, E, F, G, L for use in a lithium ion battery. The core compound M material may contain up to 90% nickel, as low as 5% cobalt and as high as 40% Mn, and then the gradient will change from one of these boundary compositions to as low as 10% Ni, 90% cobalt and 50% Mn.

In general, high power can be achieved by using thin electrodes of the compounds or blends described in this disclosure for the anode and cathode. When measuring the thickness of the electrode coating from aluminum foil, it is generally believed that thick electrodes have thicknesses above 60pm, up to about 200pm, while thinner electrodes (i.e., less than 60pm) are better configured for high power lithium ion batteries. Typically for high power, more carbon black additive is used in the electrode formulation to make it more conductive. Cathode compounds are available from several material suppliers, such as Umicore, BASF, TODA Kogyo, Ecopro, Nichia, MGL, Shanhan and Mitsubishi Chemical. Compound M is available from Ecopro and is described in its product literature as a CSG material (e.g., xLi [ Ni ]_0.8Co_0.1Mn_0.1]O₂(1-x)Li[Ni_0.46Co_0.23Mn_0.31]O₂]) Another M-type compound can also be used, for example, YK Sun in electrophoresisThe imiacata, vol 55, vol 28, p 8621-8627, all of which can be preferably mixed with the above compounds.

The compounds a to M incorporated as two or more compounds in the high-voltage cathode can preferably be coated with a surface-modifying agent. When a surface modifier is used, it is preferred, although not necessary, that each compound be coated with the same surface modifier. The surface modifier helps to improve the first cycle efficiency and rate capability of the cathode mixture. Furthermore, the use life can be increased by applying surface-modifying materials. An example of a surface modifier is Al₂O₃、Nb₂O₅、ZrO₂、ZnO、MgO、TiO₂Metal fluorides, e.g. AlF₃And a metal phosphate AlPO₄And CoPO₄. Such surface-modifying compounds have been described in earlier literature [ J.Liu et al, Journal of Materials Chemistry 20(2010) 3961-3967; ST Myung et al, Chemistry of Materials 17(2005) 3695-; S.T.Myung et al, Journal of Physical Chemistry C111 (2007) 4061-; ST Myung et al, Journal of Physical Chemistry C1154 (2010) 4710-; BC Park et al, Journal of Power Sources 178(2008) 826-; cho et al, Journal of Electrochemical Society151(2004) A1707-A1711]But use with a hybrid cathode at voltages above 4.2V has never been reported. In particular, it is beneficial to blend the surface modified compounds B, C, D, E, F, G, L and M for use in operations above 4.2V.

The cathode material is mixed with a binder and carbon black (e.g., ketjen black) or other conductive additives. NMP is commonly used to dissolve the binder, PVDF is the preferred binder for lithium ions, and lithium polymer types may have other binders. The cathode slurry is mixed to a stable viscosity, as is well known in the art. The above-mentioned compounds a-M and blends thereof are sometimes collectively referred to herein as "cathode active materials". Similarly, the anodic compound is referred to as an anode active material.

The cathode electrode can be made by mixing, for example, a cathode compound (e.g., a blend of compounds a-M or individual compounds described above) in about 94% of the cathode active material and about 2% carbon black and 3% PVDF binder. Carbon black can be ketjen black, Super P, acetylene black, and other conductive additives, which are commercially available from a variety of suppliers, including akzo nobel, Timcal, and Cabot. A slurry is formed by mixing these ingredients with NMP solvent and then coating the slurry onto both sides of an about 20 micron thick aluminum foil and drying at about 100 to 130 ℃ with the desired thickness and areal weight. The electrode is then calendered to the desired thickness and density by rollers.

The anode is prepared similarly, but in the case of graphite, about 94-96% of the anode active material is generally used, and the content of the PVDF binder is 4%. SBR binders are sometimes used for cathodes mixed with CMC, for which type of binder a relatively high amount of about 98% of the anode active material can generally be used. For the anode, carbon black may sometimes be used to improve rate performance. The anode was coated on an approximately 10 micron copper foil.

The skilled person will be able to easily mix the above-described compositions for functional electrodes.

To limit electrode expansion during charging and discharging, fibrous materials of PE, PP and carbon may be added to the electrode formulation at will. Other expansion techniques use inert ceramic particles, such as SiO, in the electrode formulation₂、TiO₂、ZrO₂Or Al₂O₃. Typically, the density of the cathode is in the range of 3 to 4g/cm³Preferably between 3.6 and 3.8g/cm³While the graphite anode is between 1.4 and 1.9g/cm³Preferably from 1.6 to 1.8g/cm³This is achieved by pressing.

Partition board

The separator needs to be an electrically insulating film interposed between the anode electrode and the cathode electrode, and should have high permeability to Li ions and high strength in tension and in the transverse direction and high penetration strength. The pore size is typically between 0.01 and 1 micron and the thickness is between 5 and 50 microns. Non-woven polyolefin sheets are commonly used, such as Polyethylene (PE), polypropylene (PP) or PP/PE/PP constructions. May be made of Al in general₂O₃The ceramic of composition is applied to the film to improve shrinkage upon heating and to improve internal short circuit protection. The cathode or anode may also be similarly coated with ceramic. The separators are available from a variety of suppliers in the industry, including Celgard, SK, Ube, Asahi Kasei, Tonen/Exxon, and WScope.

Electrolyte

Electrolytes are commonly found in industry to contain solvents and salts. The solvent is typically selected from DEC (diethyl carbonate), EC (ethylene carbonate), EMC (ethyl methyl carbonate), PC (propylene carbonate), DMC (dimethyl carbonate), 1, 3-dioxolane, EA (ethyl acetate), Tetrahydrofuran (THF). The salt is selected from LiPF₆、LiClO₄、LiAsF₆、LiBF₄The sulfur-containing or imide compound for the electrolyte includes LiCFSO₃、LiN(CF₃SO₂)₂、LiN(CF₃CF₂SO₂)₂Or by bubbling SO2 through a pre-mixed electrolyte (e.g., EC/EMC/DMC (ratio 1: 1: 1) and 1M LiPF₆) Ordinary sulfonation was carried out with other salts being LiBOB (lithium dioxalate borate), TEATFB (tetraethylammonium tetrafluoroborate), TEMEBF4 (triethylmethylammonium tetrafluoroborate). Additives for effective SEI formation, gas generation, flame retardant properties or redox shuttle capability, including BP (biphenyl), FEC, pyridine, triethyl phosphite, triethanolamine, ethylenediamine, hexaphosphoric triamide, sulfur, PS (sulfoxide sulfite), ES (ethylene sulfite), TPP (triphenyl phosphate), ammonium salts, halogen-containing solvents such as carbon tetrachloride or ethylene trifluoride, and additional CO2 gas may also be used to improve high temperature storage characteristics. For solid/gel or polymer electrolytes, PVDF-HFP, EMITFSI, LiTFSI, PEO, PAN, PMMA, PVC, any mixture of these polymers can be used with other electrolyte components to provide a gel electrolyte. Electrolyte suppliers include Cheil, Ube, Mitsubishi Chemical, BASF, Tomiyama, Guotsa-Huasong, and Novolyte.

There are some electrolytes that can be used in both supercapacitors (capacitors with electrochemical double layers) and standard lithium ion batteries. For those electrolytes, one or more ultracapacitor cores may be mixed with one or more regular lithium ion core components in the housing such that the ultracapacitor assembly functions as a motive agent and the lithium ion core components function as an energy harvesting agent.

Examples

In this example, a set of 5 cylindrical winding core members are connected in parallel with two common bus bars (positive and negative poles), similar to the MC battery configuration shown in fig. 1, but with half the core members. The negative electrode connector was attached to a tab extending from the anode foil (copper) of the jellyroll with a coated graphite electrode and the positive electrode connector of the cathode foil (aluminum) had a mixed oxide electrode structure of compound M and compound F. The nickel anode tab and the aluminum cathode tab are welded to the bus bar using spot welding or laser welding techniques. The housing and the support member are made of a plastic material (polyethylene). In this example, a cylindrical cavity of 18mm diameter and a core member of slightly smaller diameter (17.9mm) were used. The housing and the lid are made of plastic material which are ultrasonically welded together to form a gas-tight seal.

As mentioned above, the properties of the core member can be selected and varied by those skilled in the art to achieve a high energy or high power core. The following table lists three examples in which the core components of the above 5 core means examples are different and different characteristics of the MC battery can be achieved.

The present disclosure may be embodied in other specific forms without departing from its spirit or essential characteristics. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive.

Claims (25)

1. A lithium ion battery comprising:

at least two support members, each of the at least two support members comprising a plurality of cavities defined by cavity surfaces, wherein each of the plurality of cavities is configured to receive a lithium ion core member through a cavity opening;

a plurality of lithium ion core members, each of the plurality of lithium ion core members (i) comprising an anode, a cathode, a separator between the anode and the cathode, and an electrolyte, and (ii) being located in one of the plurality of cavities of the support member, and

a gas-tight enclosure (i) defining or including a common wall between two of the at least two support members to define two separate regions, and (ii) defining a first shared atmosphere region within a first of the two separate regions and a second shared atmosphere region within a second of the two separate regions;

wherein each of the lithium ion core members is surrounded along its length by a cavity surface of one of the plurality of cavities to prevent electrolyte from escaping from the cavity containing it; and

wherein the anode, cathode and electrolyte of each ion core member are in communication with the first or second shared atmosphere region through a cavity opening when positioned in the cavity of the at least two support members.

2. The lithium ion battery of claim 1, wherein the first shared atmosphere region is in communication with the second shared atmosphere region despite having the common wall.

3. The lithium ion battery of claim 1, wherein the housing comprises at least one pressure break feature.

4. The lithium ion battery of claim 1, wherein each separation region comprises at least one pressure break feature.

5. The lithium ion battery of claim 1, wherein the housing is fabricated with a clamshell configuration.

6. The lithium ion battery of claim 5, wherein the flip construction comprises symmetrically identical sidewall components.

7. The lithium ion battery of claim 1 further comprising at least one structure for controlling fluid flow from one or more of the lithium ion core members.

8. The lithium ion battery of claim 7, wherein the at least one structure is a blanket in contact with or in close proximity to one or more of the lithium ion core members.

9. The lithium ion battery of claim 7, wherein the at least one structure is made of a ceramic material configured and dimensioned to facilitate axial flow through the structure and substantially prevent lateral flow therethrough.

10. The lithium ion battery of claim 1, wherein the common wall is a partial wall that extends only a portion of a distance between a bottom and a top of the housing, or is an entire wall that extends from the bottom to the top of the housing.

11. The lithium ion battery of claim 1, wherein the at least two support members comprise a kinetic energy absorbing material.

12. The lithium ion battery of claim 1, further comprising a cavity liner in each cavity, wherein each of the cavity liners is formed of a plastic or aluminum material and receives one of the lithium ion core members.

13. The lithium ion battery of claim 1, further comprising an electrical connector located within the gas-tight enclosure, the electrical connector electrically connecting the ion core member to an electrical terminal external to the gas-tight enclosure.

14. The lithium ion battery of claim 1, wherein at least one of the at least two support members is in the form of a honeycomb structure.

15. The lithium ion battery of claim 1, wherein the gas-tight enclosure comprises a wall having a compressible element that causes an electrical short circuit of the lithium ion battery when compressed due to a force impacting the wall.

16. The lithium ion battery of claim 1, wherein the air-tight enclosure comprises a flame retardant member.

17. The lithium ion battery of claim 16, wherein the flame retardant member comprises a flame retardant mesh material attached on the exterior of the air-tight enclosure.

18. The lithium ion battery of claim 16, wherein the flame retardant member is selected from the group consisting of polyurethane foam, epoxy foam, and glass fiber wool.

19. The lithium ion battery of claim 1, further comprising a protective sleeve surrounding each of the ion core members.

20. The lithium ion battery of claim 1, wherein the electrolyte comprises at least one of a flame retardant, a gas generating agent, and a redox shuttle.

21. The lithium ion battery of claim 1 wherein at least two of the lithium ion core means are connected in parallel.

22. The lithium ion battery of claim 1 wherein at least two of the lithium ion core members are connected in series.

23. The lithium ion battery of claim 1, wherein a first set of lithium ion core members are connected in parallel, a second set of lithium ion core members are connected in parallel, and the first set of lithium ion core members and the second set of lithium ion core members are connected in series.

24. The lithium ion battery of claim 1 wherein the electrical connection of the lithium ion core member is selected from the group consisting of: (i) a parallel connection of the lithium ion core members; (ii) (ii) a series connection of the lithium ion core members, and (iii) a parallel connection of a first group of lithium ion core members, a parallel connection of a second group of lithium ion core members, and a series connection of the first group of lithium ion core members and the second group of lithium ion core members.

25. The lithium ion battery of claim 1, wherein the gas-tight enclosure defines or comprises a plurality of common walls, and wherein the gas-tight enclosure defines a separation region located on either side of each of the plurality of common walls.

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