Battery mounting assembly and procedure

Abstract

Battery holder assembly comprising: a bladder device (64) with a pocket (100) that accommodates at least one battery cell (60, 60C, 60E) of a traction battery (14), wherein the bladder device (64) provides a fluid flow path that diverges at one end of the pocket (100) into a first section (120) on a first side (112) of the pocket (100) and into a second section (124) on an opposite second side (116) of the pocket (100).

Description

TECHNICAL AREA

[0001] This disclosure relates to a battery holder. In particular, the disclosure relates to holding a battery cell of an electrified vehicle using a fluid-containing flexible bladder. GENERAL STATE OF THE ART

[0002] Electrified vehicles differ from conventional motor vehicles in that they are selectively powered using one or more electric motors supplied with energy by a traction battery. These electric motors can power the vehicles instead of, or in addition to, an internal combustion engine. Examples of electrified vehicles include hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs), fuel cell vehicles (FCVs), and battery electric vehicles (BEVs).

[0003] The traction battery is a relatively high-voltage battery that selectively supplies energy to the electric motors and other electrical consumers of the electrified vehicle. The traction battery contains a large number of interconnected battery cells that store energy. Some traction batteries hold the battery cells in place using relatively rigid retaining devices. SUMMARY

[0004] A battery mounting assembly according to an exemplary aspect of the present disclosure includes, among other things, a bladder device with a pocket that accommodates at least one battery cell of a traction battery. The bladder provides a fluid flow path that diverges at one end of the pocket into a first section on a first side of the pocket and a second section on an opposite second side of the pocket.

[0005] In a further non-restrictive embodiment of the foregoing assembly, the end is a first end and the first section and the second section converge at an opposite second end of the pocket.

[0006] In a further non-restrictive embodiment of any of the foregoing assemblies, the assembly includes the at least one battery cell within the pocket. The bladder is extended circumferentially around the entire circumference of the at least one battery cell.

[0007] In a further non-restrictive embodiment of any of the foregoing assemblies, the assembly includes the at least one battery cell within the pocket. The bladder and the at least one battery cell are pressed together.

[0008] In a further non-restrictive embodiment of any of the foregoing assemblies, the bubble device is a first bubble device and the assembly includes a second bubble device. Fluid is transmitted from a common inlet line to the first bubble device and the second bubble device.

[0009] In a further non-restrictive embodiment of any of the foregoing assemblies, the bubble device diverges at a fluid inlet to the first section and a fluid inlet to the second section, and the bubble device converges at a fluid outlet from the first section and a fluid outlet from the second section.

[0010] In a further non-restrictive embodiment of any of the foregoing assemblies, the bubble device can expand and contract.

[0011] In a further non-restrictive embodiment of any of the foregoing assemblies, the assembly includes a pump that moves a fluid through the fluid flow path.

[0012] In another non-restrictive embodiment of any of the foregoing assemblies, the pump is a peristaltic pump located upstream of the point where the fluid flow path diverges.

[0013] In a further non-limiting embodiment of any of the foregoing assemblies, the assembly includes the at least one battery cell within the pocket. The at least one battery cell has a terminal side with a terminal and a plurality of other sides oriented transversely to the terminal side. The first side of the pocket and the second side of the pocket are positioned along the other sides of the battery cell.

[0014] A battery holding method according to an exemplary aspect of the present disclosure includes, among other things, moving a fluid stream along a fluid flow path in the direction of at least one battery cell and diverging the stream into a first or second section of the fluid flow path such that the stream moves along opposite sides of the at least one battery cell.

[0015] In a further non-restrictive embodiment of the above method, the method involves converging the current from the first and second sections and moving the current away from the battery cell.

[0016] In a further non-restrictive embodiment of any of the foregoing methods, the method involves transferring thermal energy between the fluid and the battery cell to manage the thermal energy within the at least one battery cell.

[0017] In a further non-restrictive embodiment of any of the foregoing methods, the method involves surrounding the at least one battery cell with the fluid flow path in the circumferential direction.

[0018] In a further non-restrictive embodiment of any of the foregoing methods, the at least one battery cell is at least a first battery cell, and the method further comprises using a first peristaltic pump to selectively increase or decrease the current, and using a second peristaltic pump to increase or decrease a current to another fluid flow path that diverges to move along opposite sides of at least a second battery cell.

[0019] Another non-restrictive embodiment of any of the foregoing methods involves increasing or decreasing the current using the first peristaltic pump in response to a detected condition from the at least one first battery cell and separately increasing or decreasing the current using the second peristaltic pump in response to a detected condition from the at least one second battery cell.

[0020] In a further non-restrictive embodiment of any of the foregoing methods, the fluid flow path is provided by a flexible bladder.

[0021] In a further non-restrictive embodiment of any of the foregoing methods, the extension of the at least one battery cell expresses fluid from the first and second sections.

[0022] In a further non-restrictive embodiment of any of the foregoing methods, the method includes moving the fluid flow between a fluid reservoir and the first and second sections and estimating a state of the at least one battery cell based on an amount of fluid within the fluid reservoir.

[0023] In a further non-restrictive embodiment of any of the foregoing methods, the method involves holding the at least one battery cell using the first and second sections. List of characters

[0024] The various features and advantages of the disclosed examples will become apparent to a person skilled in the art from the detailed description. The figures accompanying the detailed description can be briefly described as follows: Fig. Figure 1 schematically illustrates an example powertrain for an electrified vehicle. Fig. Figure 2 illustrates a partially enlarged, perspective view of an exemplary drive battery of the powertrain. Fig. 1. Fig. Figure 3 illustrates a schematic top view of the drive battery. Fig. 3 with the housing removed. Fig. Figure 4 illustrates a perspective view of a battery cell and a bladder device of the traction battery. Fig. 2, in which the battery cell is located outside a pocket of the bladder device. Fig. Figure 5 illustrates a top view of the battery cell inside a pocket of the bubble device. Fig. 4. Fig. Figure 6 illustrates a top view of the battery cell inside a pocket of the bubble device. Fig. 3, if the battery cell moves from the position of Fig. 5 extended. Fig. Figure 7 illustrates a perspective top view of a battery cell of the traction battery. Fig. 2 according to another embodiment of the present disclosure. Fig. Figure 8 illustrates the battery cell made of Fig. 7, if the battery cell moves from the position of Fig. 7 extended. DETAILED DESCRIPTION

[0025] This disclosure relates to the retention of battery cells within a traction battery of an electrified vehicle. The battery cells are held by means of a fluid-containing bladder device. The bladder device can adapt to the expansion and contraction of the battery cells while still holding and contacting them. Fluid can be moved through the bladder device to manage thermal energy levels within the battery cell and the rest of the traction battery.

[0026] Fig. Figure 1 schematically illustrates a drive train 10 for an electrified vehicle. Although depicted as a hybrid electric vehicle (HEV), it is understood that the concepts described here are not limited to HEVs and could extend to any other electrified vehicles, including but not limited to plug-in hybrid electric vehicles (PHEVs), battery electric vehicles (BEVs), fuel cell vehicles, etc.

[0027] The powertrain 10 includes a drive battery 14 , which have a variety of battery arrangements 18 features an internal combustion engine 20 , an electric motor 22 and a generator 24 The electric motor 22 and the generator 24 These are types of electrical machines. The electric motor 22 and the generator 24They can be separate or take the form of a combined motor-generator.

[0028] In this embodiment, the drive train is 10 a power-split drivetrain that employs a first drive system and a second drive system. The first and second drive systems generate torque to drive one or more sets of vehicle drive wheels. 28 to propel. The first propulsion system includes a combination of the internal combustion engine. 20 and the generator 24 The second drive system includes at least the electric motor. 22 , the generator 24 and the drive battery 14 The electric motor 22 and the generator 24 are parts of an electric drive system of the powertrain 10 .

[0029] The internal combustion engine 20 and the generator 24can be achieved through a power transmission unit 30 , such as a planetary gear set. Of course, other types of power transmission units, including other gear sets and transmissions, can be used to connect the internal combustion engine. 20 with the generator 24 to connect. In a non-restrictive embodiment, the power transmission unit is 30 to a planetary gear set that includes a ring gear 32 , a sun wheel 34 and a support assembly 36 contains.

[0030] The generator 24 can be from the internal combustion engine 20 through the power transmission unit 30 They are driven to convert kinetic energy into electrical energy. The generator 24 Alternatively, it can serve as an electric motor to convert electrical energy into kinetic energy, thereby generating a torque on a shaft. 38is output, which is connected to the power transmission unit 30 is connected.

[0031] The hollow gear 32 the power transmission unit 30 is with a wave 40 connected by a second power transmission unit 44 with the vehicle's drive wheels 28 is connected. The second power transmission unit 44 may include a gear set containing a variety of gears 46 exhibits. Other power transmission units could be used in other examples.

[0032] The gears 46 transfer the torque from the combustion engine 20 on a differential 48 , ultimately to control the vehicle's drive wheels 28 to provide traction. The differential 48 It can include a variety of gears which transmit torque to the vehicle's drive wheels. 28enable. In this example, the second power transmission unit is 44 through the differential 48 mechanically attached to an axis 50 coupled to transfer torque to the vehicle's drive wheels 28 to distribute.

[0033] The electric motor 22 can be used selectively to control the vehicle's drive wheels 28 by applying a torque to a shaft 52 to drive, which is also connected to the second power transmission unit 44 is connected. In this embodiment, the electric motor acts 22 and the generator 24 as part of a regenerative braking system, in which both the electric motor 22 as well as the generator 24 They can be used as electric motors to output torque. For example, the electric motor 22 and the generator 24 Each cell of the drive battery outputs electrical energy.14 to recharge.

[0034] Now, with reference to Fig. 2 includes the drive battery 14 according to an exemplary non-restrictive embodiment, a plurality of individual battery cells 60 as one of the arrangements 18 , a variety of bladder devices 64 and a case 68 The battery cells 60 are arranged along an axis A. The bubble devices 64 do the battery cells 60 inside the housing 68 In particular, the exemplary bladder devices 64 a movement of the battery cells 60 relative to each other and to other areas of the traction battery 14 restrict. Holding the battery cells 60 Can aligning the battery cells 60 within the drive battery 14to facilitate, for example, attaching components to the drive battery 14 during the manufacture of the drive battery 14 .

[0035] In this example, the bladder devices consist of 64 made from a flexible polymer material, such as rubber, which defines a variable volume for holding a fluid.

[0036] Fluid can pass through the bubble devices. 64 move. Fluid moves out of an inlet pipe. 72 into the bladder devices 64 Fluid moves through an outlet pipe. 76 from the bladder devices 64 In another example, each bladder device 64 supplied by a separate line, so that each of the bladder devices 64 a part of a fluid circuit separate from the fluid circuits of the other bubble devices 64 within the drive battery 14 provides.

[0037] The bladder devices 64 The moving fluid could be a liquid or a gas. The fluid could be a coolant, such as a 50 / 50 mixture of water and ethylene glycol.

[0038] The battery cells 60 They can expand and contract during a cycle. The bladder apparatus 64 expand with the battery cells 60 out and contract with them, so that the battery cells 60 to be held further. The bladder devices 64 They contain less fluid when the battery cells 60 are extended as if the battery cells 60 have moved in together.

[0039] The exemplary case 68 includes a pair of opposing end walls 80 , a pair of opposite side walls 84 , a base plate 88 and a cover plate 92 The casing 68contains the bladder devices 64 and the battery cells 60 .

[0040] This example also includes a large number of spacers. 96 in the case 68 Included. The spacers 96 areas within the housing 68 to occupy the bladder device 64 to prevent them from moving into these areas. Regarding the spacers. 96 These could be, for example, retaining pins that secure components of the housing. 68 hold, such as the base plate 88 and the cover plate 92 .

[0041] The spacers 96 and the case 68 are relatively stiff compared to the bladder devices 64 Accordingly, a movement of the bladder devices 64 against the spacers 96 and the case 68 the spacers 96 and the case68 not.

[0042] The bladder devices 64 The battery cells contact 60 directly to the battery cells 60 to keep. Since the bladder devices 64 adapt to the expansion and contraction of the battery cells 60 The battery cells can adapt during a cycle. 60 during the cycle further from the bladder devices 64 It is understood that relatively rigid mounts may not adapt significantly to the expansion and contraction of the battery cells. 60 within the drive battery 14 can adjust.

[0043] In this exemplary drive battery 14 are six individual battery cells 60 shown, however, it could be any number of battery cells 60 can be used. Some example traction batteries 14Up to one hundred individual battery cells could be used. 60 include batteries grouped in arrangements of ten battery cells.

[0044] The exemplary battery cells 60 They have a rectangular profile. In other examples, the battery cells could be... 60 They should be cylindrical. The cells could be pouch cells, prismatic cells, cylindrical cells, etc.

[0045] Regarding the example battery cells 60 These are silicon (Si)-based battery cells. Some silicon-based battery cells have exhibited a volume expansion of more than 200% during a cycle, resulting in an axial width W of the battery cells. 60 It can increase by up to 20% during a cycle.

[0046] Other example battery cells 60, which can expand considerably during a cycle, include germanium (Ge)-based and tin (Sn)-based battery cells.

[0047] Although the bladder devices 64 In connection with the holding of silicon-based battery cells and battery cells that can expand considerably during a cycle, the teachings of this disclosure are not limited to such battery cells. The bubble devices 64 could be used to hold any type of battery cell, including lithium titanate (LTO)-based battery cells and graphite-based battery cells.

[0048] Now, with reference to the Fig. 3 and Fig. 4 represents each of the bladder devices 64 a bag 100 or an open area that contains at least one of the battery cells 60 absorbs. In this example, the bag absorbs 100one of the battery cells 60 in another example, the bag 100 for example, two of the battery cells 60 on.

[0049] In this exemplary non-restrictive embodiment, the pockets 100 each a first end 104 , a second ending 108 , a first page 112 and a second page 116 up. The first end 104 lies at the second end 108 opposite. The first page 112 is on the second side 116 opposite. The bag 100 can be dimensioned so that it generally matches the outer profile of the battery cells 60 follows, which goes into the bag 100 be recorded.

[0050] The bladder device 64 creates a fluid flow path that extends from a path inlet P I to a road outlet P o extends. At the first end 104 the bag 100The fluid flow path diverges from the inlet P I into an inlet of a first flow path section 120 and an inlet of a second flow path section 124 .

[0051] The first section 120 of the fluid flow path extends along the first side 112 the bag 100 The second section 124 of the fluid flow path extends along the second side 116 the bag 100 If the battery cell 60 in the bag 100 When positioned, the first section 120 along a first axially extending side 130 the battery cell 60 positioned and the second section 124 is along a second axially extending side 134 the battery cell 60 positioned. The first axially running side 130 and the second axially running side 134point in opposite directions.

[0052] At the second end 108 the bag 100 The current converges from an outlet of the first flow path section. 120 and an outlet of the second flow path section 124 into outlet P o .

[0053] Diverging of the fluid flow path from inlet P I in the first section 120 and the second 124 and the subsequent convergence of the fluid flow from the first section 120 and the second 124 into the exit P o This allows the fluid flow path to cover the entire circumference of the battery cell 60 to surround in a circumferential direction when the battery cell is in the pocket 100 is positioned. The bladder device 64 provides the fluid flow path and thus also surrounds the area in the pocket 100 positioned battery cell60 in a circumferential direction.

[0054] The road entrance P I takes fluid from the inlet line 72 The fluid moves from a fluid reservoir. 150 to the entrance management 72 .

[0055] In this embodiment, each of the bladder devices 64 a pump 154 , such as a peristaltic pump. The example pump 154 is located upstream of the point where the fluid flow path passes through the bubble device 64 diverges. A fluid pressure within the bubble devices. 64 can be done using the pumps 154 be adjusted. In another example, a pump is used to draw fluid from the fluid reservoir. 150 to more than one of the bladder devices 64 to move the pumps 154 In some examples, a backflow of fluid from the bubble devices may occur. 64to the entrance management 72 prevent the bladder devices from functioning 64 provided holding of the battery cells 60 could reduce it.

[0056] To control the fluid pressure in the bubble devices 64 To further control the areas near the road outlet P o have a reduced diameter, so that the fluid pressure does not pass through the path outlet P o is released and pressure is created within the bladder devices. 64 is maintained. Instead or additionally, areas near the path outlets P could be o with check valves 158 be equipped to handle the bladder devices 64 to prevent them from passing through the exits P o to empty when the pumps 154 do not provide overpressure, such as when the drive battery 14is not in operation. The check valves could instead or additionally be integrated into other areas of the fluid flow path.

[0057] Areas of the fluid flow path could also include through-flow pressure relief valves. 162 to incorporate, which prevents excessive negative pressure from being applied to the bladder devices 64 could prevent this.

[0058] In some examples, the flow through the fluid flow path is controlled by a pressure controller. 166 controlled, which is programmed to control the pumps 154 to operate the check valves 158 to operate the pressure relief valves 162 to operate or a combination of these. The pressure control 166 is programmed to control the fluid pressure within the flow path and especially within the bubble devices 64to maintain within a desired pressure range or, for example, to deliver a desired quantity of fluid through the bubble devices. 64 to move the pumps 154 could be controlled in such a way that they deliver a lower current to one or more of the bubble devices. 64 of the drive battery pack 14 allow a larger flow to one or more other bladder devices 64 of the drive battery pack 14 allow.

[0059] The pumps 154 They could, for example, be controlled in such a way that they direct the current to a bubble device. 64 in response to a detected state by the battery cell 60 , which are produced by this bladder device 64 The temperature is maintained, selectively increased or decreased. The detected state could be provided by a sensor used to measure the temperature of this battery cell. 60, a print of this battery cell 60 , to measure temperature, pressure, or any other condition. The sensor could be mounted on the battery cell. 60 The sensor could be integrated inside the pocket between the battery cell. 60 and the bladder device 64 be positioned.

[0060] Furthermore, with reference to Fig. 2 represents Fig. 5 the battery cell 60 which has a first axial width and Fig. 6 represents the battery cell 60 which are due to the expansion of the battery cell 60 exhibits a second, larger axial width. Expansion of the battery cells. 60 This can occur during normal operation due to certain anode materials that tend to expand and contract. Such materials could include silicon, lithium, tin, etc. Battery cells 60They can also occur due to an accumulation of gas inside the battery cells. 60 either over time during normal operation or over a shorter period due to a fault condition.

[0061] The expansion is mainly directed towards the first axially extending side. 130 and the second axially running side 134 , because these sides are longer than the other sides and also because the base plate 88 and the cover plate 92 an expansion of the battery cell 60 can restrict upwards and downwards.

[0062] In other words, the case 68 an expansion of the battery cells 60 limit the expansion so that it occurs along axis A in directions perpendicular to the sides 130 and 134 the battery cells 60 concentrated.

[0063] Although the case 68As shown, other examples could be different devices for limiting the expansion of the battery cells. 60 to be used in the desired directions. Straps, edging strips, etc. are other examples of such devices.

[0064] While the battery cell 60 from the position shown in FIG. 5 to the position shown in FIG. 5 Fig. As section 6 expands, the volumes of the first section will increase. 120 and the second section 124 reduced. The volume reduction corresponds to the increased thickness of the battery cell. 60 on. Although the battery cell 60 as it expands, the first page remains 112 and the second page 116 due to the pressurized fluid in the first section 120 and in the second section 124 with the battery cell 60 in contact.

[0065] The volume reduction of the first section 120 and the second section 124displaces fluid from the bubble device 64 The part from the first section 120 and the second 124 Displaced fluid increases the fluid level in the fluid reservoir. 150 .

[0066] In some examples, the fluid level in the fluid reservoir is monitored automatically, by observation, or both. An increase in the fluid level in the fluid reservoir 150 may indicate that the size of one or more of the battery cells is abnormal 60 has increased. The indication can be registered without a technician having to open the casing. 68 the drive battery 14 must open. For example, a sudden change in the fluid level in the fluid reservoir could 150 indicate a fault condition, such as rapid expansion of battery cells 60 with the drive battery 14 .

[0067] In some examples, fluid can be contained in the bubble device. 64to be used in addition to holding the battery cells 60 the heat energy levels in the battery cell 60 to manage. For example, fluid can be stored in the bubble device. 64 Heat energy from the battery cell 60 absorb when the fluid passes through the first section 120 and the second 124 This moves the battery cell. 60 cooled. The heated fluid can be cooled, for example, using a heat exchanger. 168 be cooled and then returned to the fluid supply 150 be conducted.

[0068] The fluid could also be heated so that when it passes through the bubble devices, the fluid... 64 moved the battery cells 60 heated. Furthermore, heating resistors could be installed in the bladder devices. 64 be involved in order to handle the fluid, the battery cells 60 or to heat both.

[0069] When the fluid is in the bubble devices 64 for heating or cooling the battery cells 60 When used, the pressure control 166 the speed of the individual pumps 154 adjust them so that they release different amounts of fluid through the bubble devices. 64 move. Increased fluid movement through one of the bubble devices. 64 This may be necessary, for example, if the bladder device 64 held battery cell 60 faster than the other battery cells 60 in the drive battery 14 heated. Holding the battery cells 60 Within a specific temperature range, the efficiency of the traction battery can be increased. 14 increase.

[0070] Again with reference to Fig. 2 and further with reference to the Fig. 3 to Fig. 6 include the ones for the top plate 92facing surfaces of the battery cells 60 at least two connections 170 Busbars 174 can be used to connect the 170 the battery cells 60 to connect electrically. The busbars 174 consist of a metal or metal alloy and are rigid compared to the battery cells 60 and the bladder devices 64 Although they are shown in the illustration as the cover plate 92 This could indicate one or both of the connections 170 in another area, such as the base plate 88 pointing inwards, and being connected via other busbars.

[0071] Electrical energy can pass through the busbars 174 to the battery cells 60 to or away from them. Electrical energy could also be transferred to the drive battery using busbars or other electrical connectors. 14move towards it or away from it. The battery cells 60 They could be connected electrically in series or in parallel.

[0072] Now, with reference to the Fig. 7 and Fig. There are 8 battery cells 60 in a non-restrictive variation of the foregoing embodiments within a holding device 182 positioned and then inside the pockets 100 positioned. The holding device 182 limits the expansion of the battery cells 60 , so that it is directed in an axial direction between vertically extending supports 186 the holding device 182 is concentrated. A base plate 190 and a cover plate 194 the holding device 182 limit vertical expansion of the battery cells 60 The brackets 186 connect the base plate 190 and the cover plate 194In some non-restrictive embodiments, the holding device represents 182 a basic compression level is provided by the bladder device 64 ( Fig. 4) cannot provide it alone. The battery cells 60 In some cases, compression during the cycle may benefit.

[0073] Fig. 7 represents the battery cell 60 in a less extended position than the battery cell 60 out of Fig. 8. In the battery cell 60 out of Fig. 8 is the extension in an axial direction between the vertically extending supports. 186 the holding device 182 concentrated.

[0074] The foregoing description is more illustrative than restrictive. A person skilled in the art may deduce variations and modifications of the disclosed examples that do not necessarily deviate from the core of this disclosure. Therefore, the scope of protection afforded by this disclosure can only be determined by reading the following patent claims.

Claims

[1] Battery mounting assembly comprising: a bladder device with a pocket that accommodates at least one battery cell of a traction battery, wherein the bladder provides a fluid flow path that diverges at one end of the pocket into a first section on a first side of the pocket and a second section on an opposite second side of the pocket. [2] Battery holder assembly according to claim 1, wherein the end is a first end and the first section and the second section converge at an opposite second end of the bag. [3] Battery holder assembly according to claim 1, further comprising the at least one battery cell inside the pocket, wherein the bladder is spread circumferentially around an entire circumference of the at least one battery cell and optionally wherein the at least one battery cell has a terminal side with a terminal and a plurality of other sides oriented transversely to the terminal side, wherein the first side of the pocket and the second side of the pocket are positioned along the other sides of the battery cell. [4] Battery holder assembly according to claim 1, further comprising the at least one battery cell inside the pocket, wherein the bladder and the at least one battery cell are pressed together. [5] Battery mounting assembly according to claim 1, wherein the bubble device is a first bubble device and further comprising a second bubble device, wherein fluid is transmitted from a common input line to the first bubble device and to the second bubble device. [6] Battery mounting assembly according to claim 1, wherein the bubble device diverges at a fluid inlet to the first section and a fluid inlet to the second section and the bubble device converges at a fluid outlet from the first section and a fluid outlet from the second section. [7] Battery mounting assembly according to claim 1, wherein the bubble device can expand and contract. [8] Battery mounting assembly according to claim 1, further comprising a pump which moves a fluid through the fluid flow path and optionally wherein the pump is a peristaltic pump upstream of the point where the fluid flow path diverges. [9] Battery mounting methods, comprising: Moving a fluid flow along a fluid flow path towards at least one battery cell; and Diverging of the current into a first or a second section of the fluid flow path, such that the current moves along opposite sides of the at least one battery cell. [10] Battery holding method according to claim 9, further comprising converging the current from the first and from the second section and moving the current away from the battery cell. [11] Battery holding method according to claim 9, further comprising transferring thermal energy between the fluid and the battery cell to manage thermal energy within the at least one battery cell, and optionally surrounding the at least one battery cell in the direction of circulation with the fluid flow path. [12] Battery holding method according to claim 9, wherein the at least one battery cell is at least one first battery cell and further comprising using a first peristaltic pump to selectively increase or decrease the current, and using a second peristaltic pump to selectively increase or decrease a current to another fluid flow path that diverges to move along opposite sides of the at least one second battery cell, and optionally increasing or decreasing the current with the first peristaltic pump in response to a detected condition from the at least one first battery cell and separately increasing or decreasing the current with the second peristaltic pump in response to a detected condition from the at least one second battery cell. [13] Battery holding method according to claim 9, wherein the fluid flow path is provided by a flexible bladder and optionally wherein the expansion of the at least one battery cell forces fluid out of the first and second sections. [14] Battery holding method according to claim 9, further comprising moving the fluid flow between a fluid reservoir and the first and second sections and estimating a state of the at least one battery cell based on an amount of fluid within the fluid reservoir. [15] Battery holding method according to claim 9, further comprising holding the at least one battery cell by means of the first and the second section.

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