RU197149U1 - Autonomous battery module based on lithium polymer batteries - Google Patents

Abstract

The utility model relates to the field of energy supply, namely to stand-alone battery modules based on prismatic lithium-polymer batteries. A self-contained battery module based on prismatic lithium-polymer batteries contains the same type of battery cells, vertical spacers, three electronic components, contacts, an outer case and an inner case. The battery cells are connected in series in an electric circuit and are arranged at a constant interval, providing a through section of the air cooling channels. The electronic unit provides control of parameters and leveling the unbalance of voltage of the battery cells. Vertical spacers are located between the battery cells, between the cells and the walls of the inner case. Spacers provide air cooling of the battery cells. An opening is made on the lower wall of the outer case of the battery module through which forced cooling air from the electric fan enters. The outer casing is mounted on a metal frame. Between the frame, the outer and inner bodies air channels are formed. The technical result consists in increasing the reliability of operation of an autonomous air-cooled battery module based on prismatic lithium-polymer batteries, increasing its service life and expanding the range of operating currents, while maintaining a level of protection against mechanical damage and a simple design. 7 c.p. f-ly, 4 ill.

Description

The utility model relates to the field of energy supply, more specifically to means of electric energy storage, and is intended primarily for use in transport engineering as a part of energy-supplying complexes of vehicles equipped with a traction electric drive.

The prior art lithium-ion secondary battery (RU 103675 U1, 04/20/2011), which consists of prismatic lithium-ion secondary cells connected in series into an electric circuit and separated from each other and from the walls of the battery case by dielectric spacers. Battery cells are placed in recesses of complex shape, made in spacers that are mounted on a cooled base of the battery. All components of the battery are pulled together with power pins. The method of cooling the battery cells does not provide a uniform temperature field on their entire surface, because heat transfer is carried out from a small area of the cell bottoms, and uneven heating of the batteries can lead to a decrease in electric capacity during cycling (charge / discharge).

A high-power battery is known from the prior art (RU 155156 U1, 09/20/2015), containing a block of flat lithium-polymer batteries connected in series and installed in polyamide frames equipped with holes for couplers to secure the batteries in the block and blocks in the battery. Between the batteries in the unit, metal heat sinks with an increased heat transfer surface at the ends are installed, which transfer heat to the casing walls through heat-conducting electrical insulating gaskets, and a power key board based on an aluminum base of an electronic battery monitoring and control system is installed on the battery base through a heat-conducting electrical insulating gasket. On the inner surface of the casing, a coating of heat-insulating fine-meshed foam polyurethane is coated, which makes it possible to maintain heat inside the battery at low temperatures at low discharge currents and ensure its discharge capacity up to 75% of the nominal. On the other hand, this technical solution significantly reduces the permissible discharge current of the battery and, accordingly, its capacity, at a positive ambient temperature. It should also be noted that the battery has three electronic boards: two control boards, a power switch board and a temperature sensor board, which greatly complicates the design and reduces its reliability and fault tolerance.

The prior art battery module based on lithium-polymer batteries with improved conditions for heat transfer between cells (US 2007/0037051 A1, 02/15/2007), containing the front and rear end plates and located between them in series connected in the electric circuit of the same type of battery cells of a prismatic shape , each of which is placed in the spacer with the provision of air cooling channels, as well as tightening studs that close the compressive force on the end plates. Spacers in it are installed between the battery cells in such a way that one spacer is placed between two adjacent cells, covering the cell with its three sides: the front and two side or two sides: the front and side, and these sides of the spacers contain several grooves made through The assembled battery module is formed by horizontally arranged channels for the passage of the cooling fluid.

However, in the assembled battery module, such a constructive construction of spacers, if necessary, to provide the required strength parameters, can lead to a fairly significant overlap of the front surfaces of the battery cells with jumpers between the grooves, while the air cooling channels will have a relatively small total pass-through area, this will complicate air circulation and heat dissipation . Therefore, despite the presence of air cooling channels, the heat sink system is not able to provide uniform and sufficient heat removal at maximum electric loads on the battery module, which should be attributed to its main drawback, which leads to a decrease in the resource and reliability of the module.

The prior art electric battery (US 2009/0253026 A1, 10/08/2009), containing many energy-generating elements (electrochemical cell of a lithium-ion or lithium-polymer type) packed in a flexible sealed enclosure that protects the housing from mechanical and thermal damage, made of heat-conducting material. This housing has two longitudinal elements and many transverse elements connecting these longitudinal elements, forming compartments for electrochemical cells. The specified housing includes circulation channels for the liquid coolant. A serious drawback of this design is the impossibility of ensuring a tight fit of the electrochemical cells to the transverse elements along which the liquid coolant passes. This is due to the presence of a tolerance on the thickness of the cells and the dimensions of the case, therefore, it is equally likely that there is an air gap that reduces the heat transfer rate and causes excessive heating of the cells, and that the permissible compression loads of the cells are exceeded, which can lead to mechanical damage.

The closest analogue (prototype) of the proposed utility model is a battery module based on lithium-polymer batteries (RU 142206 U1, 06/20/2014) containing the front and rear end plates and the same type of battery cells located in series between them, connected in an electric circuit, each of which placed in a spacer with air cooling channels. Spacers are made in the form of a detachable housing element composed of two pairs of opposite side racks. The front and rear covers of the module, together with the spacers, form the module housing, which protects the battery cells from possible mechanical damage during operation.

Such a design of the battery module increases the weight of the battery module, and also complicates the design with relatively non-intensive air cooling of the battery cells, which reduces the reliability of the autonomous battery module with air cooling, reduces its service life and limits the range of possible operating discharge currents.

The problem solved by the utility model is aimed at developing an effective stand-alone battery module based on lithium-polymer batteries, which has an increased resource and reliability.

The technical result consists in increasing the reliability of operation of an autonomous air-cooled battery module based on prismatic lithium-polymer batteries, increasing its service life and expanding the range of operating currents, while maintaining a level of protection against mechanical damage and a simple design.

The technical result is achieved by the fact that an autonomous battery module based on lithium-polymer batteries of a prismatic shape, containing at regular intervals providing a through section of air cooling channels, the same type of battery cells connected in series to the electric circuit, three electronic units for monitoring parameters and leveling voltage imbalance battery cells, to which the contacts of the cells are connected, is equipped with an inner casing, made in the form four plates connected to each other along the contour of the battery cells, forming two beveled side, rear and front walls, which are also connected to two longitudinally arranged strips, on which the battery cells are supported, by an outer casing made in the form of plates, forming two upper side, two lower lateral, upper rear, lower rear, upper front, lower front walls, cover and base, which are fixed on a metal frame made of profile pipes, vertical spacer located between the battery cells, as well as between the first extreme battery cell and the front wall of the inner case, between the second extreme battery cell and the rear wall of the inner case, preventing the cells from touching each other and the cells touching the front and rear walls of the inner case, the thickness fixed spacers determines the size of the air channels that provide cooling of the battery cells, as well as the air channels formed by the frame, the outer inner casings, while the walls of the outer casings are connected to a metal frame, forming a collapsible housing-protection for contacts of the battery cells and electronic units from mechanical damage, and an opening is made on the lower front wall of the outer casing of the battery module through which forcedly circulated cooling air from the electric fan mounted on this wall, and on the rear wall of the outer casing there is a hole for air outlet, and in the space between morning and outer housings in the lower part of the battery module is mounted air distributor forming a channel of variable cross section, and the additional horizontal partitions disposed between the inner and outer walls of the housings prevent occurrence of eddies in the air flow, reducing drag and increasing the intensity of heat removal.

The design of the stand-alone battery module also has the following additional differences.

- The spacers are equidistant from the side edges, the electrolyte-filled part of the battery cell with which they are fixed, and are arranged vertically, the indicated location of the spacers prevents the cells from touching each other and the cells touching the housing covers. This arrangement of the spacers provides a constant height clearance of the air gap, while at the same time not significantly reducing its cross-sectional area. A smaller number of spacers (one) will lead to uneven width (on the side where there is a spacer, the gap width is maximum, but tends to zero on the opposite side).

- Spacers are made in the form of elongated flat rectangular plates, with the wide side adjacent to the battery cells, which simplifies the manufacturing process and the assembly of the battery module due to their simple shape.

- The spacers are connected to the battery cells by an adhesive connection, and the lower and upper walls of the outer casing of the respective sides are connected to each other by a groove connection in the same way as the lower side, lower back, lower front walls and the base of the outer casing, and the upper side and upper the back, upper front walls with the cover of the outer casing, and the walls of the inner casing are connected to each other by a spike-groove system,

which simplifies the process of assembling the battery module, disassembling in the event of a battery cell malfunction, as well as reducing the weight of the stand-alone battery module by eliminating other common types of fasteners with a higher mass.

- The outer and inner cases are made of a composite material, which is based on plastics, which ensures a reduction in the mass of an autonomous battery module while maintaining the reliability of the structure, and also eliminates the possibility of shorting any electrical contact to the case.

- The walls of the outer casing are mounted on a metal frame using fasteners, like the electric fan on the front wall of the outer casing,

which ensures reliable fixation of the elements with each other and increases the protective properties during transportation and external influences.

In the drawings:

in FIG. 1 shows a general view of an autonomous battery module (isometric view);

in FIG. 2 is a view of an autonomous battery module illustrating its internal structure (isometric view);

in FIG. 3 is a view of an autonomous battery module illustrating an internal structure (side view);

in FIG. 4 shows a three-dimensional view of the battery cells assembly with spacers (isometric view).

1 - Battery Cell

2 - The protrusion of the battery cell

3 - Electrolyte-filled part of the cell

4 - Battery cell contacts

5 - Mounting plate

6 - clamping plate

7 - Electronic unit

8 - Stand

9 - Vertical spacer

10 - Wall of the inner case

11 - The upper side wall of the outer casing

12 - Lower side wall of the outer casing

13 - The upper rear wall of the outer casing

14 - Lower rear wall of the outer casing

15 - The upper front wall of the outer casing

16 - Lower front wall of the outer casing

17 - the cover of the outer casing

18 - The base of the outer casing

19 - Metal frame

20 - Fastener

21 - longitudinal bar

22 - Air distributor

23 - Horizontal partition

24 - Terminal

25 - Air inlet hole from the electric fan in the outer casing

26 - Electric fan

27 - Hole for air to escape from the outer casing.

The proposed autonomous battery module contains sequentially installed battery cells 1 of a prismatic shape with a lithium-ion polymer electrolyte.

The battery cells 1 are arranged vertically parallel to each other so that the negative and positive contacts of adjacent cells are located opposite each other. Each cell 1 contains a protrusion 2 and part 3 filled with electrolyte. The protrusion 2 of the cell on top contains an anode and a cathode, passing into contacts 4. The contacts 4 of the battery cells 1 pass through the slots in the mounting plate 5 and are fixed by clamping bars 6. The bars 6 are attached to the mounting plate by screws, which provides a clamp.

The parameters and the leveling of the unbalance of the voltage of the battery cells are controlled by three electronic units 7, the contacts of the 4 cells 1 are connected to them. They are located in the upper part of the battery module above the mounting plate 5 and are mounted on it on racks 8, which serve as fasteners.

Between all cells there are vertical spacers 9 made in the form of rectangular plates made of dielectric material, equipped with an adhesive layer on the surfaces in contact with the battery cells 1. Vertical spacers 9 provide uniform distribution of cells in the module and guarantee the presence of air channels between cells. Spacers 9 prevent the cells from touching each other. The air passing through these channels cools the cells during their operation. Spacers 9 are equidistant from the edges of the part of the battery cells filled with electrolyte 3 and are arranged vertically, with a distance between two spacers greater than from the spacer to the edge of cell 1. The glue connection simplifies the process of assembling the battery module, disassembling in the event of a battery cell malfunction, as well as reducing weight stand-alone battery module.

To direct the air flows, the battery module has an inner case made in the form of four plates connected to each other along the contour of the battery cells by a thorn-groove system, forming two side, rear and front walls 10. Spacers 9 are connected to the front and rear walls 10 which prevent the cells from touching the inner case. To protect against mechanical stresses, the battery module is equipped with an outer casing made of plates forming two upper lateral 11, two lower lateral 12, upper rear 13, lower rear 14, upper front 15, lower front 16 walls, cover 17, base 18, which mounted on a metal frame 19 made of profile pipes, using fasteners 20. The lower 12, 14, 16 and upper 11, 13, 15 walls of the outer casing, the respective sides, are connected to each other by a groove connection in the same way as the lower side 12, lower h dnyaya 14, lower front wall 16 to the base 18 of the outer housing and the top side 11 and the upper rear 13, upper front wall 15 with the lid 17 of the outer shell. The frame 19, the outer and inner cases form air channels for cooling the battery cells 1.

The battery cells 1 are supported by two longitudinally arranged strips 21, to which are connected from below the walls 10 of the inner case from the inside, forming a base. The straps 21 are supported on the frame 19 and are welded to it.

An air distributor 22 is installed in the space between the inner and outer cases at the bottom of the battery module, forming a channel of variable cross section. The side walls formed by the plates of the inner case are also beveled to form an air channel of variable cross section. Additional horizontal partitions 23 located between the walls of the inner and outer casings prevent turbulence in the air flow, reducing aerodynamic drag and increasing the heat sink intensity.

To the contacts of the first and last cells 1 using clamping strips 6 are attached terminals 24, intended for connection with the consumer and the charger.

The elements of both collapsible cases are made of composite material, which is based on plastics, which reduces the mass of an autonomous battery module while maintaining the reliability of the design, and also eliminates the possibility of shorting any electrical contact on the case.

For more intensive cooling of the battery cells 1, an opening 25 is made on the front lower 16 wall of the outer case of the battery module through which forced cooling air from the electric fan 26 enters, and on the rear bottom wall 14 of the outer case there is a hole 27 for the incoming air to exit. The fan 26 is mounted on the outer casing using fasteners 20. The dimensions of the hole 25 on the case coincide with the dimensions of the inlet (not shown) of the fan 26.

The work of the autonomous battery module is divided into two modes: the module charge and its discharge, carried out in normal mode.

The heat energy released during the cycling of the battery cells 1 is transferred from the front surfaces of the cells to the air gap between the cells 1 provided in the module. The spacers 9 form the vertical air cooling channels of the cells 1, through which air passes from the inlet 25 to the outlet 27 in the housing.

The fan 26 creates excess pressure, under the influence of which it enters the air gap between the outer and inner bodies. Passing at the bottom of the battery module, the air is evenly divided by the numerous gaps between the cells of the distributor 22. Rising from the bottom up, through the gaps between the cells, the air takes away excess thermal energy, and then goes out through the hole in the back wall into the environment.

The housing design is optimized in order to evenly distribute the coolant along the air gaps between the battery cells 1 for more uniform and efficient cooling during operation. The uniformity of cooling allows you to increase the reliability and durability of the battery module and its battery cells 1.

Since, as you know, the unbalance of individual battery cells 1 is a negative phenomenon in the operation of the module, leading to a decrease in the operating voltage and a decrease in the amount of stored energy, which reduces the electric capacity of the module and, accordingly, reduces the range of the electric vehicle, and the main reasons for the unbalance several, for example: non-identical characteristics of cells 1, determined by deviations during the production process, unequal initial state cells 1 before installing them in the module, as well as the different temperature state of cells 1, then during these modes it is very important to control the imbalance of the battery cells 1, which means the difference in the value of the remaining charge of the individual cells 1.

In the proposed module, when at least one battery cell 1 reaches the maximum / minimum value in terms of the charge / discharge value of the cell, the control unit 7 stops the charge / discharge process in accordance with the safety requirements for the operation of battery cells with a lithium-ion polymer electrolyte, which can be a fire hazard overcharge / overdischarge, characterized by the output voltage of the battery cell 1 beyond the permissible limits.

Thus, due to its design, it is possible to increase the reliability of operation of an autonomous air-cooled battery module based on prismatic lithium-polymer batteries, increase its service life and expand the range of operating currents, while maintaining a level of protection against mechanical damage and a simple design.

In addition, due to the functionality of the board 27, the competitive advantage of the proposed stand-alone battery module is the possibility of its self-diagnosis, dynamic assessment of the degree of charge, the correction of output characteristics depending on both the current state and the forecast.

In addition, due to its design, namely by reducing the number and mass of body parts, the manufacturing and assembly process of the battery module is simplified and an increase in the specific capacity of the module is achieved.

Claims (8)

1. A stand-alone battery module based on prismatic lithium-polymer batteries, which are arranged at a constant interval, providing a through section of the air cooling channels, the same type of battery cells connected in series to an electric circuit, an electronic unit for monitoring parameters and leveling the voltage unbalance of the battery cells, to which are connected cell contacts, characterized in that the battery module contains three electronic units, an inner case, made in the form of four plates connected to each other along the contour of the battery cells, forming two beveled side, rear and front walls, which are also connected to two longitudinally arranged strips, on which the battery cells are supported, the outer casing made in the form of plates, forming two upper lateral, two lower lateral, upper rear, lower rear, upper front, lower front walls, cover and base, which are fixed on a metal frame made of profile pipes, vertically spacers located between the battery cells, as well as between the first extreme battery cell and the front wall of the inner case, between the second extreme battery cell and the rear wall of the inner case, preventing the cells from touching each other and the cells touching the front and rear walls of the inner case, the thickness of the fixed spacer determines the size of the air channels providing cooling of the battery cells, as well as the air channels formed by the frame m, the outer and inner cases, while the walls of the outer case are connected to a metal frame, forming a collapsible protection case for contacts of the battery cells and electronic units from mechanical damage, and a hole is made on the lower front wall of the outer case of the battery module through which it enters circulating cooling air from an electric fan mounted on this wall, and on the rear wall of the outer casing there is an opening for air outlet, stve between the inner and outer housings in the lower part of the battery module is mounted air distributor forming a variable cross section channel, and the additional horizontal partition disposed between the inner and outer walls of the housings prevent occurrence of eddies in the air flow, reducing drag and increasing the intensity of the heat sink. 2. The stand-alone battery module according to claim 1, characterized in that the spacers are equidistant from the side edges of the electrolyte-filled part of the battery cell with which they are fixed, one vertical spacer on the edge. 3. The stand-alone battery module according to claim 1, characterized in that the spacers are made in the form of elongated flat rectangular plates of dielectric material. 4. The stand-alone battery module according to claim 1, characterized in that the spacers are connected to the battery cells by an adhesive connection. 5. The stand-alone battery module according to claim 1, characterized in that the outer and inner cases are made of composite material, which is based on plastics. 6. The stand-alone battery module according to claim 1, characterized in that the lower and upper walls of the outer casing of the respective sides are connected to each other by a groove connection in the same way as the lower side, lower back, lower front walls and the base of the outer casing, and upper side and upper back, upper front walls with the cover of the outer casing. 7. The stand-alone battery module according to claim 1, characterized in that the walls of the inner case are connected to each other by a spike-groove system. 8. The stand-alone battery module according to claim 1, characterized in that the walls of the outer casing are fixed to the metal frame using fasteners, as is the electric fan on the front wall of the outer casing.

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