Disclosure of Invention
The embodiment of the application provides a battery module, an energy storage device and electric equipment with high use safety.
In a first aspect, embodiments of the present application provide a battery module. The battery module comprises a plurality of electric cores and an elastic heat insulation piece. The plurality of battery cells are arranged along a first direction; the elastic heat insulation piece is arranged between two adjacent electric cores and comprises a heat insulation body part, a first insulating film and a second insulating film, wherein the first insulating film is attached to and coated on the heat insulation body part, the second insulating film is attached to and coated on one side, deviating from the heat insulation body part, of the first insulating film, the material strength of the second insulating film is smaller than that of the first insulating film, and the melting point of the first insulating film is smaller than that of the second insulating film.
In the battery module provided by the application, the elastic heat insulating piece is used for insulating the adjacent two battery cores and preventing the thermal runaway diffusion of the battery cores, wherein the elastic heat insulating piece can continuously insulate the adjacent two battery cores, and the service life of the elastic heat insulating piece is prolonged, so that the outer surface of the heat insulating body part of the elastic heat insulating piece is firstly adhered with a first insulating film with stronger strength, and the possibility of tearing due to abrasion and scratch caused by weaker strength of the material of the insulating film is reduced or avoided when the first insulating film seals the heat insulating body part, and dust in the heat insulating material in the heat insulating body part or exposed particles are further prevented from generating sparks with static electricity in the space of the battery module, thereby effectively improving the safety of the battery module. In addition, a layer of second insulating film with higher melting point is added on the outer surface of the first insulating film, which is far away from the heat insulation body part, and the second insulating film is more resistant to high temperature compared with the first insulating film, so that dust in the heat insulation material in the heat insulation body part is prevented from flying or particles are prevented from being exposed after the first insulating film is melted down due to overhigh working temperature or thermal runaway of the battery core, and the safety performance of the battery module is improved. Through first insulating pad pasting and the thermal-insulated body portion of second insulating pad pasting laminating, prevent that the dust of the insulating material the inside in the thermal-insulated body portion from flying upward or the particulate matter exposes, improve elastic heat insulating part life, and then when adopting elastic heat insulating part to insulate against heat two adjacent electric cores, ensure that elastic heat insulating part can last to insulate against heat the electric core, prevent electric core thermal runaway diffusion, promote battery module's safety in utilization. In addition, the elastic heat insulating piece has elasticity, that is, the elastic heat insulating piece has elastic compression deformation space, and a certain expansion gap can be provided for the battery cell.
In one possible embodiment, aerogel is disposed within the thermally insulating body portion.
In the battery module provided by the application, the aerogel can play a role in heat insulation, the heat insulation body part is provided with an elastic compression deformation space, a certain expansion gap is provided for the battery cell, and in one possible implementation mode, the first insulation film contains Polyethylene (PE); the second insulating film contains Polyimide (PI).
According to the battery module provided by the application, compared with the second insulating film containing the PI material, the strength of the first insulating film containing the PE material is higher, the first insulating film can be prevented from being scratched and torn by the heat insulation body part, the melting point of the first insulating film containing the PE material is lower, when the temperature of the battery cell is higher than 100 ℃, the first insulating film is easy to melt, dust in the heat insulation material in the heat insulation body part flies or particles are exposed and spark is generated by static electricity in a space of the battery module, therefore, the second insulating film with a higher melting point is adhered and coated on the outer surface of the first insulating film, which is far away from the heat insulation body part, and the second insulating film can not melt under the condition that the battery cell works at a high temperature of 180-200 ℃ (about 100 ℃), so that the heat insulation film and the heat insulation material in the heat insulation body part can be better protected by the second insulating film with high temperature resistance, the sealing film on the outer surface of the heat insulation part is prevented from melting or scratching, the service life of the heat insulation part is prolonged, the heat insulation part is prevented from being continuously used for the battery cell, the safety of the heat insulation module is guaranteed, the heat insulation performance is kept from being out of the heat insulation part, and the safety of the battery is reduced.
In one possible implementation manner, the battery module further comprises a bracket, wherein the bracket is arranged between two adjacent electric cores, and a containing space is formed in the bracket; the elastic heat insulation piece is arranged in the accommodating space.
In the battery module provided by the application, the bracket is used for fixedly clamping two adjacent battery cells, so that the battery cells are fixed. A bracket is arranged between two adjacent electric cores arranged along the first direction, and can provide a containing space for placing the elastic heat insulation piece; the accommodation space is also used for positioning the position of the elastic heat insulating piece, so that the elastic heat insulating piece is prevented from falling off or sliding out or the positions of the elastic heat insulating pieces between two adjacent electric cores are prevented from being different, the heat insulating uniformity is poor, and the cycle performance of the battery module is influenced. The cell returns in the charge-discharge process and appears the phenomenon that expands and the back is retracted, and the support that is provided with accommodation space can provide the expansion space for two adjacent cells, and in addition, the elastic heat-proof component has the elastic compression deformation space, also can provide certain inflation clearance for the cell, reduces the inflation pressure between the cell, reduces the false triggering of explosion-proof valve, promotes the safety in utilization and the life of battery module.
In one possible implementation manner, the support includes a first cross bar, a second cross bar, and two vertical bars, the first cross bar with the second cross bar sets up relatively along the second direction, two vertical bars set up relatively along the third direction, first direction the second direction with the third direction mutually perpendicular, first cross bar, one of them the vertical bar, second cross bar and another the montant is fixed connection in proper order and is formed the accommodation space, along the first direction, the first length that the accommodation space extends is L1, the second length that the elastic heat insulation piece extends is L2, the first length L1 that the accommodation space extends with the second length L2 that the elastic heat insulation piece extends satisfies: L1-L2 is less than or equal to 2.3mm and less than or equal to 3.1mm.
In the battery module provided by the application, the first cross rod, one of the vertical rods, the second cross rod and the other vertical rod are sequentially and fixedly connected to form the square bracket, the bracket is used for fixedly clamping two adjacent electric cores, and the first cross rod, the second cross rod and the two vertical rods jointly form the accommodating space, wherein the length of the elastic heat insulation part extending along the first direction is smaller than the length of the accommodating space extending along the first direction. If the difference between the first length L1 extending from the accommodating space and the second length L2 extending from the elastic heat insulating member is smaller than 2.3mm (i.e., L1-L2<2.3 mm), the expansion space reserved for the battery cells on both sides is too small, and the expanded battery cells are easily extruded by the elastic heat insulating member to increase the expansion pressure of the battery cells when the battery cells expand within a safe expansion distance in the charging and discharging process of the battery cells, so that the use safety of the battery module is reduced. If the difference between the first length L1 extending from the accommodating space and the second length L2 extending from the elastic heat insulating piece is larger than 3.1mm (namely L1-L2 is larger than 3.1 mm), the interval between the elastic heat insulating piece and the electric cores at two sides is overlarge, after the expansion phenomenon occurs in the electric core charging and discharging process, the electric cores at two sides cannot exchange heat with the elastic heat insulating piece due to overlarge interval between the elastic heat insulating piece and the electric cores at two sides, and the electric cores are not subjected to certain constraint action in the expansion process, so that the electric core surface excessively protrudes under the condition of being in a safe expansion distance, the electrolyte infiltration effect is poor, the lithium precipitation phenomenon occurs on pole pieces in the electric cores, the service life of the electric cores is reduced, the interval between the elastic heat insulating piece and the electric cores at two sides is overlarge, the electric cores at two sides cannot exchange heat with the elastic heat insulating piece, and the heat insulating effect is poor. Along the first direction, the first length L1 of the extending accommodating space and the second length L2 of the extending elastic heat insulating piece meet the requirement that L1-L2 is less than or equal to 2.3mm and less than or equal to 3.1mm, a certain space is reserved after the elastic heat insulating piece is installed in the accommodating space, the elastic heat insulating piece and two adjacent electric cores can be ensured to have a certain interval by adjusting the installation position of the elastic heat insulating piece, the extrusion of the elastic heat insulating piece to the electric cores expanding in a safe expansion distance is avoided, the expansion pressure of the electric cores is reduced, and the use safety of the battery module is improved; and the elastic heat insulation piece can also play a role in restraining the excessive protrusion of the surface of the battery cell in the safe expansion distance in the charge and discharge process of the battery cell, so that the battery cell is kept smooth in the charge and discharge process, the electrolyte wetting effect is better, the lithium precipitation can be reduced, and the charge and discharge cycle times of the battery cell are further prolonged.
In one possible implementation manner, along the second direction, the first height of the extending accommodating space is H1, the second height of the extending elastic heat insulation part is H2, and the first height H1 of the extending accommodating space and the second height H2 of the extending elastic heat insulation part meet that 1.5mm is less than or equal to H1-H2 is less than or equal to 5.0mm; along the third direction, the first width of accommodation space extension is W1, the second width of elastic heat insulating element extension is W2, the first width of accommodation space extension W1 with the second width of elastic heat insulating element extension W2 satisfies: W1-W2 is less than or equal to 1.5mm and less than or equal to 5.0mm.
In second direction and third direction, all reserve certain deformation space between accommodation space and the elastic heat insulating part, do not need high operation accuracy alright place the elastic heat insulating part in accommodation space, and the elastic heat insulating part is elastically deformable, extrude the elastic heat insulating part and can make the elastic heat insulating part warp when two adjacent electric cores expand relatively, the second height H2 of elastic heat insulating part along the second direction and the second width W2 along the third direction can increase, need reserve certain deformation space, if do not reserve deformation space for the elastic heat insulating part, can lead to its deformation degree of difficulty big, the expansion space of reservation for the electric core can reduce, influence the expansion of electric core, and then lead to the inside atmospheric pressure increase of electric core to influence the life of electric core. According to the application, the deformation space is reserved in the second direction and the third direction, so that the elastic heat insulation piece is easier to deform by extrusion of the battery cell, the expansion of the battery cell is not influenced, and the service life of the battery cell is prolonged.
Further, if the difference between the first height H1 of the accommodating space and the second height H2 of the elastic heat insulating element is smaller than 1.5mm (i.e., H1-H2 is smaller than 1.5 mm), the deformation space of the elastic heat insulating element along the second direction is too small, which affects the deformation of the elastic heat insulating element and thus indirectly affects the expansion gap of the battery cell, and affects the cycle performance of the battery cell; if the difference between the height H1 of the accommodating space and the second height H2 of the elastic heat insulating element is larger than 5.0mm (namely H1-H2 is larger than 5.0 mm), the deformation space of the elastic heat insulating element along the second direction is overlarge, and the heat insulating effect of the elastic heat insulating element is poor; along the second direction, the first height H1 of the accommodating space and the second height H2 of the elastic heat insulation member satisfy: H1-H2 which is less than or equal to 1.5mm and less than or equal to 5.0mm, so that the elastic heat insulation piece is easier to deform, has good heat insulation effect and ensures the cycle performance of the battery cell.
Similarly, if the difference between the first width W1 of the accommodating space and the second width W2 of the elastic heat insulating element is smaller than 1.5mm (i.e. W1-W2<1.5 mm), the deformation space of the elastic heat insulating element along the third direction is too small, which affects the deformation of the elastic heat insulating element and thus indirectly affects the expansion gap of the battery cell, and affects the cycle performance of the battery cell; if the difference between the first width W1 of the accommodating space and the second width W2 of the elastic heat insulating element is larger than 5.0mm (namely W1-W2 is larger than 5.0 mm) along the third direction, the deformation space of the elastic heat insulating element along the third direction is too large, and the heat insulating effect of the elastic heat insulating element is poor; along the third direction, the first width W1 of the accommodating space and the second width W2 of the elastic heat insulating member satisfy: W1-W2 is less than or equal to 1.5mm and less than or equal to 5.0mm, so that the elastic heat insulation piece is easier to deform, has good heat insulation effect, and ensures the cycle performance of the battery cell.
In one possible embodiment, the battery cell includes an end cap assembly including a first surface, the first surface being a surface of the end cap assembly facing away from the first rail, and the second rail protruding from the first surface in the second direction.
In the battery module provided by the application, the bracket is arranged between two adjacent battery cells, the second cross rod protrudes out of the first surface of the end cover assembly, and the second cross rod can be abutted against the side edge of the end cover assembly to prevent the edge of the end cover assembly from warping or peeling.
In one possible embodiment, the second rail includes a second surface, the second surface being a surface of the second rail facing away from the first rail, and along the second direction, a perpendicular distance H3 between the second surface and the first surface is H3, the perpendicular distance H3 between the second surface and the first surface satisfying: h3 is more than or equal to 0.3mm and less than or equal to 0.6mm.
In the battery module provided by the application, if the vertical distance H3 between the second surface of the second cross rod and the first surface of the end cover is smaller than 0.3mm along the second direction, the second cross rod is easily jacked by the edge of the end cover assembly which is warped or stripped, so that the fixing effect of the bracket on the battery cell is weakened; if the vertical distance H3 between the second surface of the second cross rod and the first surface of the end cover assembly is greater than 0.6mm, the protruding distance of the second cross rod is too large, which hinders the installation of other components in the battery module, such as the wire harness isolation plate needs to be installed on the surface of the end cover assembly, which faces away from the first cross rod, and if the protruding distance of the second cross rod is too large, the wire harness isolation plate will be tilted. Along the second direction, a vertical distance H3 between the second surface of the second cross bar and the first surface of the end cap assembly satisfies: 0.3mm is less than or equal to H3 is less than or equal to 0.6mm, ensures that the second cross rod can firmly restrict in end cover assembly's edge, leads to the second cross rod to be jacked when preventing that end cover assembly edge from taking place to warp, and avoids the too big installation that influences other parts in the battery module of second cross rod protrusion distance.
In one possible implementation manner, the battery cell includes an end cover assembly, a housing and an electrode assembly, the housing forms a containing space, the electrode assembly is contained in the containing space, the end cover assembly covers the housing and is installed in two battery cells of the same bracket, and an orthographic projection of a joint of the end cover assembly and the housing along the first direction is located in the second cross rod.
In the battery module provided by the application, the orthographic projection of the joint of the end cover assembly and the shell along the first direction is positioned in the second cross rod, so that part of the structure of the second cross rod can shield the joint of the end cover assembly and the shell, the joint of the end cover assembly and the shell can be ensured to be protruded by the second cross rod, the phenomenon that the welding part between the end cover and the shell of the battery core is torn due to the fact that the second cross rod is extruded by excessive bulges between two battery cores positioned on two sides of the second cross rod and the side face of the shell, facing the bracket, is extruded by the second cross rod is avoided, and the use safety of the battery module is improved.
In one possible implementation manner, the support further comprises a plurality of reinforcing ribs, the plurality of reinforcing ribs are arranged on the second cross rod, a plurality of concave parts extending along the third direction are formed on the second cross rod, the concave parts are recessed from one surface, close to the battery cell, of the second cross rod towards the direction away from the battery cell, and one reinforcing rib is formed between two adjacent concave parts.
In the battery module provided by the application, the plurality of reinforcing ribs are arranged on the second cross rod, so that the structural strength of the second cross rod is enhanced, the second cross rod is effectively limited to be jacked up due to excessive swelling of two battery cells at two sides of the second cross rod, the second cross rod is ensured to be stably limited at the edge of the end cover assembly, the tearing phenomenon at the welding position between the end cover assembly and the shell of the battery cell is avoided, and the use safety of the battery module is improved.
In one possible implementation manner, the bracket further comprises a first positioning clamping piece and a second positioning clamping piece, wherein the first positioning clamping piece is arranged at two opposite ends of the first cross rod along the third direction, and the first positioning clamping piece supports the battery cell; the second positioning clamping piece is arranged at two opposite ends of the second cross rod along the third direction, the battery cell comprises an end cover assembly, and the second positioning clamping piece is abutted to the end cover assembly.
In the battery module provided by the application, the first positioning clamping pieces are arranged at the opposite ends of the first cross rod along the third direction, namely, the first positioning clamping pieces are arranged at the connection positions of the first cross rod and the two vertical rods respectively, and the number of the first positioning clamping pieces is two; the second positioning clamping piece is arranged at two opposite ends of the second cross rod along the third direction, namely, the second positioning clamping piece is arranged at the joint of the second cross rod and the two vertical rods respectively, two corners of the support are provided with first positioning clamping pieces, two other corners are provided with second positioning clamping pieces, the first positioning clamping pieces and the second positioning clamping pieces can protect four corners of the battery cell, the end cover assembly is prevented from being warped and stripped at the four corners of the battery cell, the stability of connection of the battery cell is ensured, and the use safety of the battery module is further guaranteed.
In one possible implementation manner, the first positioning clamping piece comprises a first plate body and a second plate body which are arranged at an included angle, the projection of the first plate body along the second direction is located at two opposite sides of the projection of the first cross rod along the first direction, the first plate body is arranged at a first end part of the vertical rod, which is away from the second cross rod, along the third direction, and is arranged at one side of the first cross rod, which is away from the accommodating space, along the second direction, the first plate body extends from the first end part along the third direction towards the accommodating space, and the first plate body supports the battery cell; along the third direction the projection of second plate body is located the montant projection is in the relative both sides of first direction, the second plate body is located the montant is in the third direction deviates from the one side of accommodation space, and from first plate body with the junction of second plate body is orientation the second horizontal pole extends.
In the battery module provided by the application, the first positioning clamping piece is formed by the first plate body and the second plate body which are arranged at an included angle, for example, the first plate body and the second plate body can be mutually perpendicular. The projection of the first plate body along the second direction is located on two opposite sides of the projection of the first cross rod along the second direction (specifically, two opposite sides of the projection of the first cross rod along the first direction), so that the first plate body can support two electric cores located on two opposite sides of the first cross rod along the first direction. Similarly, the projection of the second plate body along the third direction is located on two opposite sides of the projection of the vertical rod along the third direction (specifically, two opposite sides of the vertical rod along the first direction), so that the second plate body can limit the bottoms of two electric cores on two sides of the first transverse rod in the third direction, the bottoms of the electric cores are one ends, deviating from the end cover assembly, of the electric cores, the electric cores are prevented from deviating from the range limited by the support, and the support is ensured to firmly clamp and fix the two electric cores.
In a possible implementation manner, the second positioning clamping piece comprises a third plate body and a fourth plate body which are arranged at an included angle, the projection of the third plate body along the second direction is located at two opposite sides of the projection of the second cross rod along the first direction, the third plate body is arranged at the second end part of the vertical rod, which is away from the first cross rod along the second direction, and extends from the second end part towards the accommodating space along the third direction, and one surface of the third plate body, which is towards the first cross rod, is abutted against the end cover assembly; the projection of the fourth plate body is located along the third direction the projection of the montant is in the opposite sides of the first direction, the fourth plate body is located the montant is in the one side of deviating from the accommodation space in the third direction, and from the junction of the third plate body with the fourth plate body towards the direction of first horizontal pole extends.
In the battery module provided by the application, the second positioning clamping piece is formed by the third plate body and the fourth plate body which are arranged at an included angle, for example, the third plate body and the fourth plate body can be mutually vertical. The projection of the third plate body along the second direction is located on two opposite sides of the projection of the second cross rod along the second direction (specifically, two opposite sides of the projection of the second cross rod along the first direction), so that one surface of the third plate body, which faces the first cross rod, can be abutted against the surfaces of two battery cells on two opposite sides of the second cross rod along the first direction, and warping and stripping of the edges of end covers of the battery cells are prevented. Similarly, the projection of the fourth plate body along the third direction is located at two opposite sides of the projection of the vertical rod along the third direction (specifically, two opposite sides of the vertical rod along the first direction), so that the fourth plate body can limit the tops of two electric cores at two sides of the second cross rod in the third direction, wherein the tops of the electric cores are one ends, close to the end cover assembly, of the electric cores, the electric cores are prevented from falling out of the range limited by the bracket, and the bracket is ensured to firmly clamp and fix the two electric cores.
In one possible implementation manner, the second positioning clamping piece further comprises a first clamping portion, the first clamping portion extends from the end portion, away from the fourth plate body, of the third plate body in the third direction towards the direction away from the first cross rod, the first clamping portion is provided with a clamping groove and a guiding inclined plane, an opening of the clamping groove is away from the accommodating space in the third direction, the battery module further comprises a cover body, the cover body is provided with a second clamping portion, and the second clamping portion stretches into the clamping groove along the guiding inclined plane to be connected with the first clamping portion in a matched mode.
In the battery module provided by the application, the first clamping part is arranged at the end part of the third plate body far away from the fourth plate body in the third direction, namely, the first clamping part and the fourth plate body are arranged at the opposite ends of the third plate body along the third direction, and the first clamping part is closer to the battery cell than the fourth plate body along the third direction, so that the clamping groove and the guide inclined plane formed by the first clamping part cannot protrude out of the side surface of the battery cell, and after the first clamping part is matched and connected with the second clamping part on the cover body, the size of the cover body of the battery module can be reduced, the volume of the battery module is further reduced, and the energy density of the battery module is improved.
In one possible embodiment, the battery module further includes a wire harness isolation board, and a distance between the two first clamping portions along the third direction is greater than a width of the wire harness isolation board extending.
In the battery module provided by the application, the distance between the two first clamping parts positioned at the two ends of the second cross rod along the third direction is larger than the extending width of the wire harness isolation plate, so that the wire harness isolation plate is positioned between the two first clamping parts, and when the second clamping parts on the cover body are matched and connected with the corresponding first clamping parts, the cover body can cover the wire harness isolation plate.
In one possible implementation manner, the battery cell has a first side surface and a second side surface opposite to each other along the third direction, the number of the vertical rods is two, the vertical rod near the first side surface has a third side surface, the vertical rod near the second side surface has a fourth side surface, the third side surface and the fourth side surface are located on opposite sides of the accommodating space along the third direction, and in the third direction, gaps are formed between the first side surface and the third side surface, and between the second side surface and the fourth side surface, a third width of the gap extending along the third direction is W3, and a third width W3 of the gap satisfies: w3 is more than or equal to 0.5mm and less than or equal to 0.7mm.
In the battery module provided by the application, along the third direction, the two vertical rods of the bracket are contracted inwards relative to the battery core, a gap is formed, insulating glue can be filled in the gap, the bracket is fixedly connected with the side plate of the battery module, the connection strength between the bracket and the side plate of the battery module is improved, and the structural stability of the battery module is improved. In addition, if the third width W3 of the gap extending along the third direction is smaller than 0.5mm, the space formed by the gap is too small, the volume of the insulating glue filled in the gap is too small, the connection strength between the vertical rod and the side plate is reduced, and the side plate is easy to fall off; if the gap extends along the third direction by a width W3 of more than 0.7mm, the gap is formed in an oversized space, and the volume of the insulating glue filled in the gap is oversized, so that the weight of the insulating glue is overweight, the insulating glue is easy to fall off, and the connection strength between the side plate and the vertical rod is further caused. The third width W3 of the gap extending in the third direction satisfies: w3 is less than or equal to 0.5mm and less than or equal to 0.7mm, the falling phenomenon of insulating glue when filling in the gap is reduced or avoided, the connection strength between the vertical rod and the side plate is improved, and the structural stability of the battery module is improved.
In one possible implementation manner, the vertical rod has a first projection in the second direction, the first projection is formed by enclosing a first straight line segment, a second straight line segment and two arc line segments, the first straight line segment is larger than the second straight line segment, the first straight line segment and the second straight line segment are located on two opposite sides of the first projection in the third direction, and the two arc line segments are located on two opposite sides of the first projection in the first direction.
In the battery module provided by the application, the first straight line section is larger than the second straight line section, namely, the plane where the first straight line section is located is larger than the plane where the second straight line section is located, wherein the plane where the first straight line section is located is connected with the side plate through the insulating adhesive, so that the connection strength of the side plate and the vertical rod is improved. The two arc sections can be used for being matched with the electric core arranged on two opposite sides of the bracket, so that heat-conducting glue is filled between the electric core and the surface where the arc sections are positioned, the bracket and the electric core are connected in an adhesive mode, and heat dissipation of the electric core is achieved.
In a possible embodiment, the bracket further comprises a groove, the groove is near the connection of the vertical rod and the second transverse rod, and the projection shape of the groove in the second direction is arc-shaped.
In the battery module provided by the application, the bracket is an injection molding part, the projection shape of the groove extending along the second direction is arc-shaped, and the groove is close to the joint of the vertical rod and the second transverse rod, so that after demoulding and cooling are carried out on the joint of the second transverse rod and the vertical rod, local position shrinkage can not occur, the bracket is prevented from being distorted and deformed due to shrinkage, and the structural strength of the bracket is improved.
In one possible implementation manner, the plurality of electric cores are arranged along the first direction to form an electric core group, the battery module further comprises side plates, the side plates are installed on two sides of the electric core group along the third direction, the side plates are arranged between the first positioning clamping piece and the second positioning clamping piece, and the distance between the first positioning clamping piece and the second positioning clamping piece along the second direction is larger than the extending height of the side plates.
In the battery module provided by the application, the distance between the first positioning clamping piece and the second positioning clamping piece is larger than the extending height of the side plate along the second direction, and after the battery module is assembled with the battery core and the bracket, the assembly gap of the side plate is reserved, so that the side plate is convenient to be adhered to the vertical rod of the bracket.
In a second aspect, embodiments of the present application provide an energy storage device comprising a battery module according to the first aspect.
According to the energy storage device provided by the application, the elastic heat insulation piece is used for insulating the adjacent two electric cores and preventing the electric cores from thermal runaway diffusion, wherein the elastic heat insulation piece can be used for continuously insulating the adjacent two electric cores, so that the service life of the elastic heat insulation piece is prolonged, therefore, the outer surface of the heat insulation body part of the elastic heat insulation piece is firstly adhered with a first insulating film with stronger material strength, and the possibility of tearing due to abrasion and scratch caused by weaker material strength of the insulating film is reduced or avoided when the first insulating film seals the heat insulation body part, and dust in the heat insulation material in the heat insulation body part or exposed particles are further prevented from generating sparks with static electricity in a battery module space, so that the safety of the battery module is effectively improved. In addition, a layer of second insulating film with higher melting point is added on the outer surface of the first insulating film, which is far away from the heat insulation body part, and the second insulating film is more resistant to high temperature compared with the first insulating film, so that dust in the heat insulation material in the heat insulation body part is prevented from flying or particles are exposed after the first insulating film is melted down due to overhigh working temperature or thermal runaway of the battery core, and the safety performance of the battery module is improved. Through first insulating pad pasting and the thermal-insulated body portion of second insulating pad pasting laminating, prevent that the dust of the insulating material the inside in the thermal-insulated body portion from flying upward or the granule exposes, improve elastic heat insulating part life, and then when adopting elastic heat insulating part to insulate against heat two adjacent electric cores, ensure that elastic heat insulating part can last to insulate against heat the electric core, prevent electric core thermal runaway diffusion, promote battery module's safety in utilization. In addition, the elastic heat insulating piece has elasticity, that is, the elastic heat insulating piece has elastic compression deformation space, and a certain expansion gap can be provided for the battery cell.
In a third aspect, an embodiment of the present application provides a powered device, where the powered device includes an energy storage device as described in the second aspect, and the energy storage device is configured to supply power to the powered device.
According to the electric equipment, the elastic heat insulation piece is used for insulating the adjacent two electric cores and preventing the electric cores from thermal runaway diffusion, wherein the elastic heat insulation piece can be used for continuously insulating the adjacent two electric cores, and the service life of the elastic heat insulation piece is prolonged, so that the outer surface of the heat insulation body part of the elastic heat insulation piece is stuck with the first insulating film with stronger strength, the possibility of tearing due to abrasion and scratch caused by weaker strength of the insulating film material when the first insulating film seals the heat insulation body part is reduced or avoided, dust in the heat insulation material in the heat insulation body part is further prevented from flying or particles are further prevented from being exposed, and sparks are generated with static electricity in a battery module space, so that the safety of the battery module is effectively improved. In addition, a layer of second insulating film with higher melting point is added on the outer surface of the first insulating film, which is far away from the heat insulation body part, and the second insulating film is more resistant to high temperature compared with the first insulating film, so that dust in the heat insulation material in the heat insulation body part is prevented from flying or particles are exposed after the first insulating film is melted down due to overhigh working temperature or thermal runaway of the battery core, and the safety performance of the battery module is improved. The first insulating film and the second insulating film are used for bonding the heat insulation body part, dust in heat insulation materials in the heat insulation body part is prevented from flying or particles are exposed, the service life of the elastic heat insulation piece is prolonged, when the elastic heat insulation piece is used for insulating heat of two adjacent electric cores, the elastic heat insulation piece is ensured to be capable of continuously insulating heat of the electric cores, thermal runaway diffusion of the electric cores is prevented, and the use safety of the battery module is improved. In addition, the elastic heat insulating piece has elasticity, that is, the elastic heat insulating piece has elastic compression deformation space, and a certain expansion gap can be provided for the battery cell.
Detailed Description
The following description of the embodiments of the present application will be made clearly and fully with reference to the accompanying drawings, in which it is evident that the embodiments described are only some, but not all embodiments of the application. All other embodiments, based on the embodiments of the application, which are apparent to those of ordinary skill in the art without inventive faculty, are intended to be within the scope of the application.
The following description of the embodiments refers to the accompanying drawings, which illustrate specific embodiments in which the application may be practiced. Directional terms, such as "upper", "lower", "front", "rear", "left", "right", "inner", "outer", "side", etc., are used herein with reference to the attached drawings only, and thus are used for better, more clear description and understanding of the present application, rather than to indicate or imply that the device or element being referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as limiting the present application.
Furthermore, the numbering of the components itself, e.g., "first," "second," etc., herein is merely used to distinguish between the described objects and does not have any sequential or technical meaning. The term "coupled" as used herein includes both direct and indirect coupling (coupling), unless otherwise indicated.
Because of the strong timeliness and space properties of energy required by people, in order to reasonably utilize the energy and improve the utilization rate of the energy, one energy form needs to be stored by one medium or equipment and then converted into another energy form, and the energy is released in a specific energy form based on future application. It is well known that the main way to generate green electric energy is to develop green energy sources such as photovoltaic, wind power and the like to replace fossil energy sources. At present, the generation of green electric energy generally depends on photovoltaic, wind power, water potential and the like, but wind energy, solar energy and the like generally have the problems of strong intermittence and large fluctuation, which can cause unstable power grid, insufficient peak electricity consumption, too much electricity consumption and unstable voltage can cause damage to the electric power, so that the problem of 'wind abandoning and light abandoning' possibly occurs due to insufficient electricity consumption requirement or insufficient power grid acceptance, and the problem needs to be solved by relying on energy storage. The energy is converted into other forms of energy through physical or chemical means and is stored, the energy is converted into electric energy when needed and released, in short, the energy storage is similar to a large-scale 'charge pal', the electric energy is stored when the photovoltaic and wind energy are sufficient, and the stored electric power is released when needed.
Taking electrochemical energy storage as an example, the present solution provides an energy storage device 1000, in which a chemical battery is disposed in the energy storage device 1000, and chemical elements in the chemical battery are mainly used as an energy storage medium, and a charging and discharging process is accompanied with chemical reaction or change of the energy storage medium.
The present energy storage (i.e. energy storage) application scenario is wider, including aspects such as power generation side energy storage, grid side energy storage, renewable energy grid-connected energy storage, user side energy storage, etc., the types of the corresponding energy storage device 1000 include:
(1) The large energy storage container applied to the energy storage scene at the power grid side can be used as a high-quality active and reactive power regulation power supply in the power grid, so that the load matching of electric energy in time and space is realized, the renewable energy consumption capability is enhanced, and the large energy storage container has great significance in the aspects of standby of a power grid system, relieving peak load power supply pressure and peak regulation and frequency modulation;
(2) The main operation modes of the small and medium-sized energy storage electric cabinet applied to the industrial and commercial energy storage scenes (banks, shops and the like) at the user side and the household small-sized energy storage box applied to the household energy storage scene at the user side are peak clipping and valley filling. Because of the large price difference of the electricity charge at the peak-valley position according to the electricity consumption requirement, after the energy storage equipment is arranged by a user, in order to reduce the cost, the energy storage cabinet/box is charged usually in the electricity price valley period; and in the peak period of electricity price, the electricity in the energy storage equipment is released for use, so that the purpose of saving electricity charge is achieved. In addition, in remote areas and areas with high occurrence of natural disasters such as earthquake, hurricane and the like, the household energy storage device is equivalent to the fact that a user provides a standby power supply for the user and the power grid, and inconvenience caused by frequent power failure due to disasters or other reasons is avoided.
In the embodiment of the present application, a household energy storage scene in user side energy storage is taken as an example for illustration, fig. 1 is a schematic view of a scene of an energy storage device 1000 provided in an embodiment of the present application, and the energy storage device 1000 is not limited to the household energy storage scene.
As shown in fig. 1, the present application provides a household energy storage system, which includes an electric energy conversion device (photovoltaic panel 2000), a user load (street lamp 3000 a), a user load (household appliance 3000 b), and the like, and an energy storage device 1000, wherein the energy storage device 1000 is a small-sized energy storage box and can be installed on an outdoor wall through a wall-hanging manner. Specifically, the photovoltaic panel 2000 may convert solar energy into electric energy during a low electricity price period, and the energy storage device 1000 is used for storing the electric energy and supplying the electric energy to electric devices such as the street lamp 3000a and the household appliance 3000b for use during a high electricity price period, or supplying power during a power failure/power outage of the power grid.
It is understood that the energy storage device 1000 may include, but is not limited to, a battery cell, a battery module, a battery pack, a battery system, etc. When the energy storage device 1000 is a single battery, it may be a prismatic battery.
Referring to fig. 2, 3 and 4, the energy storage device 1000 includes a battery module 100 according to an embodiment of the application, and the battery module 100 includes a plurality of battery cells 10 and an elastic heat insulation member 30. The plurality of battery cells 10 are arranged in the first direction a. The elastic heat insulating piece 30 is arranged between two adjacent electric cores 10, the elastic heat insulating piece 30 comprises a heat insulating body part 31, a first insulating adhesive film 33 and a second insulating adhesive film 35, the first insulating adhesive film 33 is attached to and coated on the heat insulating body part 31, the second insulating adhesive film 35 is attached to and coated on one side, deviating from the heat insulating body part 31, of the first insulating adhesive film 33, the material strength of the second insulating adhesive film 35 is smaller than that of the first insulating adhesive film 33, and the melting point of the first insulating adhesive film 33 is smaller than that of the second insulating adhesive film 35.
The first direction a is a longitudinal direction of the battery module 100, as shown in fig. 2. The second direction B is the height direction of the battery module 100, as shown in fig. 2. The third direction C is the width direction of the battery module 100, as shown in fig. 2, and the first direction a, the second direction B, and the third direction C are perpendicular to each other.
In the battery module 100, the energy storage device 1000 and the electric equipment provided by the application, the elastic heat insulation member 30 is used for insulating two adjacent battery cells 10 and preventing the battery cells 10 from thermal runaway diffusion, wherein the elastic heat insulation member 30 is ensured to continuously insulate the two adjacent battery cells 10, so that the service life of the elastic heat insulation member 30 is prolonged, therefore, a layer of first insulating adhesive film 33 with stronger material strength is adhered to the outer surface of the heat insulation body 31 of the elastic heat insulation member 30, and when the first insulating adhesive film 33 seals the heat insulation body 31, the possibility of tearing due to abrasion and scratch caused by weaker material strength of the insulating adhesive film is reduced or avoided, dust or particles in the heat insulation material in the heat insulation body 31 are further prevented from being exposed, and sparks are generated with static electricity in the battery module space, so that the safety of the battery module 100 is effectively improved. In addition, a layer of second insulating film 35 with a higher melting point is added on the outer surface of the first insulating film 33 facing away from the heat-insulating body 31, and the second insulating film 35 is more resistant to high temperature than the first insulating film 33, so that dust or particles in the heat-insulating material in the heat-insulating body 31 are prevented from flying or being exposed after the first insulating film 33 is melted down due to overhigh working temperature or thermal runaway of the battery cell 10, and the safety performance of the battery module 100 is improved. The first insulating film 33 and the second insulating film 35 are used for adhering the heat insulation body part 31, so that dust in the elastic heat insulation piece 30 is prevented from flying, the service life of the elastic heat insulation piece 30 is prolonged, and when the elastic heat insulation piece 30 is used for insulating heat of two adjacent battery cells 10, the elastic heat insulation piece 30 is ensured to continuously insulate the battery cells 10, the thermal runaway diffusion of the battery cells 10 is prevented, and the use safety of the battery module 100 is improved. In addition, the elastic heat insulating member 30 has elasticity, that is, the elastic heat insulating member 30 has elastic compression deformation space, which can provide a certain expansion gap for the battery cell 10.
The material strength of the insulating film (including the first insulating film 33 and the second insulating film 35) refers to the ability of the insulating film to resist damage (breakage), for example, tensile strength, compressive strength, shear strength, bending strength, and the like.
The first insulating film 33 is directly adhered to and coated on the outer surface of the heat insulating body 31, wherein the battery cell 10 is square, and the heat insulating body 31 is also square, so that the elastic heat insulating member 30 can insulate the whole side surface of the battery cell 10. If the material strength of the first insulating film 33 is smaller than that of the second insulating film 35, when the first insulating film 33 is used to seal the heat-insulating body 31, the first insulating film 33 is easily torn by the corners of the heat-insulating body 31, so that dust or particles in the heat-insulating material in the heat-insulating body 31 are flying or exposed, and the service life of the elastic heat-insulating member 30 is reduced. The material strength of the first insulating film 33 is set to be greater than that of the second insulating film 35, so that when the first insulating film 33 is attached to and covers the heat-insulating body 31, the heat-insulating body 31 is not easy to tear due to the abrasion of the corners of the heat-insulating body 31, and the use safety of the elastic heat-insulating member 30 is improved.
When the second insulating film 35 is attached to and coats the outer surface of the first insulating film 33, which is far away from the heat-insulating body 31, the first insulating film 33 performs primary film sealing treatment on the heat-insulating body 31, so that the material strength of the second insulating film 35 can be set smaller than that of the first insulating film 33, when the second insulating film 35 is attached to and coats the outer surface of the first insulating film 33, which is far away from the heat-insulating body 31, the first insulating film 33 is not easy to be exposed due to tearing of the sealing film, dust or particles in the heat-insulating material in the heat-insulating body 31 are further prevented from being exposed, the use safety of the elastic heat-insulating piece 30 is improved, the use safety of the battery module 100 is further effectively improved, the manufacturing cost of the elastic heat-insulating piece 30 can be effectively reduced, and the manufacturing cost of the battery module 100 is further reduced.
In one possible embodiment, aerogel is disposed within the insulating body portion 31. It can be appreciated that aerogel is a heat insulating material in the heat insulating body 31, and the aerogel can perform a heat insulating function, and make the heat insulating body 31 have an elastic compression deformation space, so as to provide a certain expansion gap for the battery cell 10.
In one possible embodiment, the first insulating film 33 contains PE; the second insulating film 35 contains PI.
The first insulating film 33 comprising PE material has a higher material strength than the second insulating film 35 comprising PI material, the first insulating film 33 can be prevented from being scratched and torn by the heat-insulating body portion 31, while the first insulating film 33 comprising PE material has a lower melting point, when the temperature of the battery cell 10 is higher than 100 ℃, the first insulating film 33 is easily melted, so that dust or particles in the heat-insulating material in the heat-insulating body portion 31 are flying or exposed to generate sparks with static electricity in the space of the battery module 100, and therefore, the second insulating film 35 having a higher melting point is adhered and coated on the outer surface of the first insulating film 33 facing away from the heat-insulating body portion 31, under the condition that the melting point of the second insulating film 35 is 180-200 ℃ and the battery cell 10 works at a high temperature (about 100 ℃), the second insulating film 35 cannot be melted, so that the heat-resistant second insulating film 35 can better protect the heat-insulating materials in the first insulating film 33 and the heat-insulating body part 31, the sealing film on the outer surface of the elastic heat-insulating member 30 is prevented from being melted or scratched and torn, the service life of the elastic heat-insulating member 30 is prolonged, the elastic heat-insulating member 30 is ensured to continuously insulate the battery cell 10, the safety performance of the battery module 100 is reduced due to thermal runaway diffusion of the battery cell 10 working at a high temperature, and the use safety of the battery module 100 is improved.
Referring to fig. 5 and 6, in one possible embodiment, the battery module 100 further includes a bracket 50, the bracket 50 is disposed between two adjacent battery cells 10, and the bracket 50 forms a receiving space 51; the elastic heat insulator 30 is disposed in the accommodating space 51.
The bracket 50 is used for fixing and tightening two adjacent battery cells 10, and plays a role in fixing the battery cells 10. A bracket 50 is disposed between two adjacent cells 10 arranged in the first direction a, and the bracket 50 may provide a receiving space 51 in which the elastic heat insulating member 30 is placed; the accommodating space 51 is also used for positioning the elastic heat insulating element 30, so that the elastic heat insulating element 30 is prevented from falling off or sliding out or the elastic heat insulating element 30 between two adjacent battery cells 10 is prevented from being positioned differently, which results in poor heat insulating uniformity and influences the cycle performance of the battery module 100. The battery cells 10 are expanded and retracted after expansion in the charge and discharge process, the bracket 50 provided with the accommodating space 51 can provide expansion space for two adjacent battery cells 10, in addition, the elastic heat insulation piece has elastic compression deformation space and can also provide a certain expansion clearance for the battery cells, so that the expansion pressure between the battery cells 10 is reduced, the false triggering of an explosion-proof valve is reduced, and the use safety of the battery module 100 and the service life of the battery module 100 are improved.
Referring to fig. 6, in one possible embodiment, the bracket 50 includes a first cross bar 52, a second cross bar 53, and two vertical bars 54, where the first cross bar 52 and the second cross bar 53 are disposed opposite to each other along a second direction B, the two vertical bars 54 are disposed opposite to each other along a third direction C, the first direction a, the second direction B, and the third direction C are perpendicular to each other, the first cross bar 52, one of the vertical bars 54, the second cross bar 53, and the other vertical bar 54 are sequentially and fixedly connected to form a containing space 51, a first length extending from the containing space 51 is L1, a second length extending from the elastic heat insulation member 30 is L2, and a first length L1 extending from the containing space 51 and a second length L2 extending from the elastic heat insulation member 30 satisfy: L1-L2 is less than or equal to 2.3mm and less than or equal to 3.1mm.
The first cross rod 52, one of the vertical rods 54, the second cross rod 53 and the other vertical rod 54 are sequentially and fixedly connected to form a square bracket 50, the bracket 50 is used for fixedly clamping two adjacent battery cells 10, and the first cross rod 52, the second cross rod 53 and the two vertical rods 54 jointly form a containing space 51, wherein the second length L2 of the elastic heat insulation member 30 extending along the first direction A is smaller than the first length L1 of the containing space 51 extending along the first direction A. If the difference between the first length L1 of the accommodating space 51 extending and the second length L2 of the elastic heat insulator 30 extending along the first direction a is smaller than 2.3mm (i.e., L1-L2<2.3 mm), the expansion space reserved for the battery cells 10 on both sides is too small, and the expanded battery cells 10 are easily extruded by the elastic heat insulator 30 to increase the expansion pressure of the battery cells 10 during the expansion within the safe expansion distance in the charge and discharge process of the battery cells 10, so that the use safety of the battery module 100 is reduced. If the difference between the first length L1 extending from the accommodating space 51 and the second length L2 extending from the elastic heat insulating member 30 along the first direction a is greater than 3.1mm (i.e., L1-L2>3.1 mm), the interval between the elastic heat insulating member 30 and the battery cells 10 on both sides is too large, after the expansion phenomenon occurs in the charging and discharging process of the battery cells 10, the interval between the elastic heat insulating member 30 and the battery cells 10 on both sides is too large, and the expansion process of the battery cells 10 is not restricted to a certain extent, so that the surface of the battery cells 10 excessively protrudes under the condition of being within the safe expansion distance, the electrolyte infiltration effect is poor, the lithium precipitation phenomenon occurs on the pole pieces in the battery cells 10, the service life of the battery cells 10 is reduced, and the interval between the elastic heat insulating member 30 and the battery cells 10 on both sides is too large, so that the battery cells 10 on both sides cannot exchange heat with the elastic heat insulating member 30, and the heat insulating effect is poor. The first length L1 of the accommodating space 51 extending along the first direction a and the second length L2 of the elastic heat insulator 30 extending satisfy: 2.3mm is less than or equal to L1-L2 is less than or equal to 3.1mm, a certain space is reserved after the accommodating space 51 is provided with the elastic heat insulation piece 30, a certain interval is reserved between the elastic heat insulation piece 30 and two adjacent battery cells 10 by adjusting the installation position of the elastic heat insulation piece 30, the extrusion of the elastic heat insulation piece 30 to the battery cells 10 expanding within a safe expansion distance is avoided, the expansion pressure of the battery cells 10 is reduced, and the use safety of the battery module 100 is improved; and the elastic heat insulation piece 30 can also play a role in restraining the excessive protrusion of the surface of the battery cell 10 in the safe expansion distance in the charge and discharge process of the battery cell 10, so that the battery cell 10 is kept smooth in the charge and discharge process, the electrolyte wetting effect is better, the lithium precipitation can be reduced, and the charge and discharge cycle times of the battery cell 10 are further prolonged.
In a typical cell design, after the cells 10 are assembled, in view of expansion occurring within a reasonable range during the operation of the cells 10, a certain expansion gap needs to be reserved between adjacent cells 10 and between the cells 10 and other contact structures, in the present application, a difference L3 between a length of the adjacent cells 10 extending along the first direction a and a length of the elastic heat insulation member 30 extending along the first direction a is a difference between a first length L1 of the accommodating space 51 extending along the first direction a and a second length L2 of the elastic heat insulation member 30 extending along the first direction a (i.e. a difference of l3=l1-L2), where L3 is a safe expansion distance range of the cells 10 during the operation. For example, if the difference l3=2.3 mm, the range of the safe expansion distance of the battery cell 10 during operation is 0mm or more and 2.3mm or less. If the difference l3=2.5, the range of the safe expansion distance of the battery cell 10 during the operation is greater than or equal to 0mm and less than or equal to 2.5mm.
In addition, in the design parameters of the battery cell 10, a parameter based on the special structure of the battery cell 10 to correspondingly realize special performance, for example, the battery cell 10 may have a separately designed and differentiated installation expansion distance K, where the safety expansion distance K is used to represent the maximum expansion distance of the battery cell 10 under normal operation, and then a difference L3 between the parameter K and a first length L1 of the bracket 50 extending along the first direction a and a second length L2 of the elastic heat insulation member 30 along the first direction a satisfies: 0.5mm < 2K-L3 < 1mm, that is, the absolute value of the difference between 2K and the difference L3 is 0.5mm or more and 1mm or less. If the value of |2k-l3| is greater than 1mm, the distance between the battery cell 10 and the elastic heat insulation member 30 is too large, the battery cell 10 is not subject to a certain constraint action in the expansion process, so that excessive protrusion of the battery cell 10 is easily caused under the condition that the battery cell 10 is within the safe expansion distance, and the service life of the battery cell 10 is reduced. If the value of |2k-l3| is less than 0.5mm, the interval between the battery cell 10 and the elastic heat insulator 30 is too small, and even if the battery cell 10 expands within a safe expansion distance, the expanded battery cell 10 is easily extruded by the elastic heat insulator 30 to cause an increase in expansion pressure of the battery cell 10, and the safety performance of the battery module 100 is degraded. In the present application, the difference L3 between the parameter K and the first length L1 of the bracket 50 extending along the first direction a and the first length L1 of the elastic heat insulating member 30 along the first direction a satisfies: the battery cell 10 is restrained to a certain extent in the expansion process by 0.5mm less than or equal to |2K-L3| less than or equal to 1mm, so that the battery cell 10 is kept flat in the charge and discharge process, the electrolyte infiltration effect is better, lithium precipitation can be reduced, and the charge and discharge cycle times of the battery cell 10 are prolonged. And excessive extrusion is not caused to the elastic heat insulator 30, so that the expansion pressure of the battery cell 10 is reduced, and the safety performance of the battery module 100 is improved.
In one possible embodiment, along the second direction B, the height of the accommodating space 51 extends is H1, the second height of the elastic heat insulating element 30 extends is H2, and the first height H1 of the accommodating space 51 and the second height H2 of the elastic heat insulating element 30 extend satisfy: H1-H2 is less than or equal to 1.5mm and less than or equal to 5.0mm; along the third direction C, the first width of the accommodating space 51 extending is W1, the second width of the elastic heat insulating member 30 extending is W2, and the first width W1 of the accommodating space 51 extending and the second width W2 of the elastic heat insulating member 30 extending satisfy: W1-W2 is less than or equal to 1.5mm and less than or equal to 5.0mm.
In the second direction B and the third direction C, a certain deformation space is reserved between the accommodating space 51 and the elastic heat insulating element 30, the elastic heat insulating element 30 can be placed in the accommodating space 51 without high operation precision, the elastic heat insulating element 30 is elastically deformable, when two adjacent electric cores 10 are relatively expanded, the elastic heat insulating element 30 is extruded to deform the elastic heat insulating element 30, the second height H2 of the elastic heat insulating element 30 along the second direction B and the second width W2 of the elastic heat insulating element 30 along the third direction C can be increased, a certain deformation space is required to be reserved, if the deformation space is not reserved for the elastic heat insulating element 30, the deformation difficulty is high, the expansion space reserved for the electric core 10 can be reduced, the expansion of the electric core 10 is influenced, and the service life of the electric core 10 is further influenced by the increase of the air pressure inside the electric core 10. According to the application, the deformation space is reserved in the second direction B and the third direction C, so that the elastic heat insulation piece 30 is easier to be extruded and deformed by the battery cell 10, the expansion of the battery cell 10 is not influenced, and the service life of the battery cell 10 is prolonged.
Further, if the difference between the first height H1 of the accommodating space 51 and the second height H2 of the elastic heat insulating element 30 is smaller than 1.5mm (i.e. H1-H2<1.5 mm), the deformation space of the elastic heat insulating element 30 along the second direction B is too small, which affects the deformation of the elastic heat insulating element 30 and thus indirectly affects the expansion gap of the battery cell 10, and affects the cycle performance of the battery cell 10; if the difference between the first height H1 of the accommodating space 51 and the second height H2 of the elastic heat insulating element 30 is greater than 5.0mm (i.e., H1-H2>5.0 mm) along the second direction B, the deformation space of the elastic heat insulating element 30 along the second direction B is too large, and the heat insulating effect of the elastic heat insulating element 30 is poor; along the second direction B, the first height H1 of the accommodating space 51 and the second height H2 of the elastic heat insulating member 30 satisfy: H1-H2 which is less than or equal to 1.5mm and less than or equal to 5.0mm, so that the elastic heat insulation piece 30 is easier to deform, has good heat insulation effect and ensures the cycle performance of the battery cell 10.
Similarly, if the difference between the first width W1 of the accommodating space 51 and the second width W2 of the elastic heat insulating element 30 is smaller than 1.5mm (i.e. W1-W2<1.5 mm), the deformation space of the elastic heat insulating element 30 along the third direction C is too small, which affects the deformation of the elastic heat insulating element 30 and thus indirectly affects the expansion gap of the battery cell 10, and affects the cycle performance of the battery cell 10; if the difference between the first width W1 of the accommodating space 51 and the second width W2 of the elastic heat insulating member 30 is greater than 5.0mm (i.e., W1-W2>5.0 mm) along the third direction C, the deformation space of the elastic heat insulating member 30 along the third direction C is too large, and the heat insulating effect of the elastic heat insulating member 30 is poor; along the third direction C, the first width W1 of the accommodating space 51 and the second width W2 of the elastic heat insulating member 30 satisfy: W1-W2 is less than or equal to 1.5mm and less than or equal to 5.0mm, so that the elastic heat insulation member 30 is easier to deform, has good heat insulation effect, and ensures the cycle performance of the battery cell 10.
Referring to fig. 3 and 7, in one possible embodiment, the battery cell 10 includes an end cap assembly 11, the end cap assembly 11 includes a first surface 111, the first surface 111 is a surface of the end cap assembly 11 facing away from the first rail 52, and the second rail 53 is disposed protruding from the first surface 111 along the second direction B.
The battery cell 10 further includes a case 12 and an electrode assembly 13, wherein the case 12 is formed with a receiving space 121, and the electrode assembly 13 is received in the receiving space 121. The end cap assembly 11 includes a top patch 114 and an end cap 115, the end cap 115 is covered on the housing 12 and seals the accommodating space 121 of the housing 12, the top patch 114 is disposed on a surface of the end cap 115 facing away from the electrode assembly 13, and the first surface 111 is a surface of the top patch 114 exposed on the end cap 115. Wherein the second cross bar 53 protrudes from the top patch 114 to avoid the risk of electrical shorting of the exposed metal surface of the end cap 115 due to warping or peeling of the top patch 114.
Referring to fig. 8, illustratively, the front projection of the junction of the end cap assembly 11 and the housing 12 along the first direction a is located within the second cross bar 53. Specifically, the front projection of the junction of the top patch 114 and the housing 12 along the first direction a is located in the second cross bar 53.
The orthographic projection of the junction of end cover assembly 11 and casing 12 along first direction A is located second horizontal pole 53 for the junction of end cover assembly 11 and casing 12 can be sheltered from to the partial structure of second horizontal pole 53, ensures that second horizontal pole 53 can bulge the junction of end cover assembly 11 and casing 12, in order to avoid being located the excessive bulge between two electric cores 10 of second horizontal pole 53 both sides and extrudees second horizontal pole 53, and the tearing phenomenon appears in the junction between end cover assembly 11 and the casing 12 that second horizontal pole 53 extrusion casing 12 is directed towards the side of support 50, promotes the safety in utilization of battery module 100.
Illustratively, a portion of the structure of the second rail 53 protrudes from the first surface 111, and a portion of the second rail 53 protruding from the first surface 111 abuts against a side edge of the top patch 114.
The support 50 is disposed between two adjacent cells 10, the second cross bar 53 protrudes from the first surface 111 of the end cap assembly 11, and the second cross bar 53 can abut against the side edge of the top patch 114, so as to prevent the edge of the top patch 114 from warping or peeling.
In one possible embodiment, the second rail 53 includes a second surface 531, the second surface 531 being a surface of the second rail 53 facing away from the first rail 52, and the vertical distance H3 between the second surface 531 and the first surface 111 along the second direction B is H3, the vertical distance H3 between the second surface 531 and the first surface 111 being such that: h3 is more than or equal to 0.3mm and less than or equal to 0.6mm.
If the vertical distance H3 between the second surface 531 of the second cross bar 53 and the first surface 111 of the end cap assembly 11 is smaller than 0.3mm along the second direction B, the second cross bar 53 is easily lifted by the edge of the end cap assembly 11 that is warped or peeled, so that the fixing effect of the bracket 50 on the battery cell 10 is weakened; if the vertical distance H3 between the second surface 531 of the second cross bar 53 and the first surface 111 of the end cap assembly 11 is greater than 0.6mm, the protruding distance of the second cross bar 53 is too large, which hinders the installation of other components in the battery module 100, such as the wire harness isolation board 70, which is required to be installed on the surface of the end cap assembly 11 facing away from the first cross bar 52, and if the protruding distance of the second cross bar 53 is too large, the wire harness isolation board 70 will be tilted. Along the second direction B, the perpendicular distance H3 between the second surface 531 of the second cross bar 53 and the first surface 111 of the end cap assembly 11 satisfies: h3 is less than or equal to 0.3mm and less than or equal to 0.6mm, ensures that the second cross rod 53 can be firmly limited at the edge of the end cover assembly 11, prevents the second cross rod 53 from being jacked up when the edge of the end cover assembly 11 is warped, and prevents the protruding distance of the second cross rod 53 from being excessively large to influence the installation of other components in the battery module 100.
Referring to fig. 6, in a possible embodiment, the bracket 50 further includes a plurality of reinforcing ribs 55, where the plurality of reinforcing ribs 55 are disposed on the second cross bar 53. The second cross bar 53 is formed with a plurality of recesses 533 extending in the third direction C, the recesses 533 are recessed from a surface of the second cross bar 53 adjacent to the battery cell 10 in a direction away from the battery cell 10, and a reinforcing rib 55 is formed between two adjacent recesses 533.
It should be noted that, the second cross bar 53 is provided with the battery cells 10 on two opposite sides of the first direction a, the second cross bar 53 is formed with the plurality of concave portions 533 on two opposite sides of the first direction a, and if the two opposite sides of the second cross bar 53 in the first direction a are left and right sides, respectively, one surface of the second cross bar 53 near the left battery cell 10 is a left side surface, the plurality of concave portions 533 on the left side are concave in a direction away from the left battery cell 10. The surface of the second cross bar 53 near the right cell 10 is lateral, and the plurality of right recesses 533 are recessed in a direction away from the right cell 10.
One reinforcing rib 55 is formed between two adjacent recesses 533, and a plurality of reinforcing ribs 55 are spaced apart on the second cross bar 53 to reinforce the structural strength of the second cross bar 53.
The second cross rod 53 is provided with a plurality of reinforcing ribs 55, the structural strength of the second cross rod 53 is enhanced, the second cross rod 53 is jacked up due to excessive bulging of the two battery cells 10 on two sides of the second cross rod 53, the second cross rod 53 is ensured to be firmly limited at the edge of the end cover assembly 11, the tearing phenomenon at the welding position between the end cover assembly 11 and the shell of the battery cell 10 is avoided, and the use safety of the battery module 100 is improved.
In one possible embodiment, the bracket 50 further includes a first positioning clip 56 and a second positioning clip 57, the first positioning clip 56 being disposed at opposite ends of the first cross bar 52 along the third direction C, the first positioning clip 56 supporting the cell 10; the second positioning clamping pieces 57 are arranged at two opposite ends of the second cross rod 53 along the third direction C, and the second positioning clamping pieces 57 are abutted against the end cover assembly 11.
The first positioning clamping pieces 56 are arranged at two opposite ends of the first cross rod 52 along the third direction C, namely, the first positioning clamping pieces 56 are arranged at the connecting positions of the first cross rod 52 and the two vertical rods 54 respectively, and the number of the first positioning clamping pieces 56 is two; the second positioning clamping pieces 57 are arranged at two opposite ends of the second cross rod 53 along the third direction C, namely, the second positioning clamping pieces 57 are arranged at the connection positions of the second cross rod 53 and the two vertical rods 54 respectively, on the whole, two corners of the support 50 are provided with the first positioning clamping pieces 56, the other two corners are provided with the second positioning clamping pieces 57, the first positioning clamping pieces 56 and the second positioning clamping pieces 57 can protect four corners of the battery cell 10, the end cover assembly 11 is prevented from being warped and peeled off at the four corners of the battery cell 10, the connection stability of the battery cell 10 is ensured, and the use safety of the battery module 100 is further ensured.
Referring to fig. 6 and 9, in one possible embodiment, the first positioning clip 56 includes a first plate 561 and a second plate 563 disposed at an included angle, the projection of the first plate 561 along the second direction B is located on two opposite sides of the projection of the first cross bar 52 in the first direction a, the first plate 561 is disposed on a first end 543 of the vertical rod 54 facing away from the second cross bar 53 along the third direction C, and is disposed on a side of the first cross bar 52 facing away from the accommodating space 51 along the second direction B, the first plate 561 extends from the first end 543 toward the accommodating space 51 along the third direction C, and the first plate 561 supports the battery cell 10; the projection of the second plate 563 along the third direction C is located at two opposite sides of the projection of the vertical rod 54 in the first direction a, and the second plate 563 is disposed at one side of the vertical rod 54 away from the accommodating space 51 in the third direction C and extends from the connection point of the first plate 561 and the second plate 563 toward the second cross rod 53.
The projection along a certain direction in the present application may be an orthographic projection on a plane perpendicular to the certain direction. For example, the projection of the first plate 561 along the second direction B may be: the first plate 561 is orthographic projected on a plane perpendicular to the second direction B.
The first positioning clip 56 is formed by a first plate 561 and a second plate 563 disposed at an angle, for example, the first plate 561 and the second plate 563 may be perpendicular to each other. The projection of the first board 561 along the second direction B is located on two opposite sides of the projection of the first cross bar 52 along the second direction B (specifically, two opposite sides of the projection of the first cross bar 52 along the first direction a), so that the first board 561 can support two battery cells 10 located on two opposite sides of the first cross bar 52 along the first direction a. Similarly, the projection of the second plate 563 along the third direction C is located on two opposite sides of the projection of the vertical rod 54 along the third direction C (specifically, two opposite sides of the vertical rod 54 along the first direction a), so that the second plate 563 can limit the bottoms of the two battery cells 10 on two sides of the first cross rod 52 in the third direction C, wherein the bottom of the battery cell 10 is one end of the battery cell 10 facing away from the end cap assembly 11, preventing the battery cell 10 from being separated from the range defined by the bracket 50, and ensuring that the bracket 50 can firmly clamp and fix the two battery cells 10.
Referring to fig. 6 and 10, in one possible embodiment, the second positioning clip 57 includes a third plate 571 and a fourth plate 573 disposed at an included angle, the projection of the third plate 571 along the second direction B is located on two opposite sides of the projection of the second cross bar 53 in the first direction a, the third plate 571 is disposed at a second end 544 of the vertical bar 54 away from the first cross bar 52, and extends from the second end 544 toward the accommodating space 51 along the third direction C, and one surface of the third plate 571 facing the first cross bar 52 abuts against the end cover assembly 11; the projection of the fourth plate 573 along the third direction C is located on two opposite sides of the projection of the vertical rod 54 in the first direction a, and the fourth plate 573 is disposed on one surface of the vertical rod 54 away from the accommodating space 51 in the third direction C and extends from the connection position of the third plate 571 and the fourth plate 573 toward the direction of the first cross rod 52.
The second positioning clip 57 is formed by a third plate 571 and a fourth plate 573 that are disposed at an included angle, for example, the third plate 571 and the fourth plate 573 may be perpendicular to each other. The projection of the third plate 571 along the second direction B is located on two opposite sides of the projection of the second cross bar 53 along the second direction B (specifically, two opposite sides of the projection of the second cross bar 53 along the first direction a), so that one surface of the third plate 571 facing the first cross bar 52 can abut against the surfaces of two electric cores 10 on two opposite sides of the second cross bar 53 along the first direction a, so as to prevent the edge of the end cap assembly 11 of the electric core 10 from warping and peeling. Similarly, the projection of the fourth plate 573 along the third direction C is located on two opposite sides of the projection of the vertical rod 54 along the third direction C (specifically, two opposite sides of the vertical rod 54 along the first direction a), so that the fourth plate 573 can limit the tops of the two battery cells 10 on two sides of the second cross rod 53 in the third direction C, wherein the top of the battery cell 10 is one end of the battery cell 10 near the end cover assembly 11, preventing the battery cell 10 from being separated from the range defined by the bracket 50, and ensuring that the bracket 50 can firmly clamp and fix the two battery cells 10.
Referring to fig. 10, 11 and 12, in one possible embodiment, the second positioning clip 57 further includes a first clipping portion 575, the first clipping portion 575 extends from an end of the third plate 571 away from the fourth plate 573 in the third direction C towards a direction away from the first cross bar 52, the first clipping portion 575 has a clipping slot 5751 and a guiding inclined plane 5753, an opening of the clipping slot 5751 faces away from the accommodating space 51 in the third direction C, the battery module 100 further includes a cover 60, the cover 60 is provided with a second clipping portion 61, and the second clipping portion 61 extends into the clipping slot 5751 along the guiding inclined plane 5753 to be connected with the first clipping portion 575 in a matching manner.
For example, the second clamping portion 61 may be a through hole adapted to the first clamping portion 575, where the clamping groove 5751 and the guiding inclined plane 5753 together form a clamping hook, and the clamping hook is clamped in the through hole and buckled on a side wall of the through hole, so as to realize the matched connection between the first clamping portion 575 and the second clamping portion 61.
The first clamping portion 575 is disposed at the end portion of the third plate body 571, far away from the fourth plate body 573, in the third direction C, that is, the first clamping portion 575 and the fourth plate body 573 are disposed at two opposite ends of the third plate body 571 along the third direction C, and in the third direction C, the first clamping portion 575 is closer to the battery cell 10 than the fourth plate body 573, so that the first clamping portion 575 forms a clamping groove 5751 and a guiding inclined plane 5753 and does not protrude out of the side surface of the battery cell 10, and after the first clamping portion 575 is matched and connected with the second clamping portion 61 on the cover body 60, the size of the cover body 60 of the battery module 100 can be reduced, the volume of the battery module 100 is further reduced, and the energy density of the battery module 100 is improved.
Referring to fig. 12, in one possible embodiment, the battery module 100 further includes a harness isolation plate 70, and a distance between the two first clamping portions 575 in the third direction C is greater than a width of the harness isolation plate 70 extending.
Referring to fig. 6, it can be understood that, in one bracket 50, two opposite ends of the second cross bar 53 along the third direction C are disposed on the second positioning clamping members 57, and two second positioning clamping members 57 are provided, and each second positioning clamping member 57 is provided with a first clamping portion 575.
Along the third direction C, the distance between the two first clamping portions 575 located at two ends of the second cross bar 53 is greater than the extending width of the wire harness isolation board 70, so that the wire harness isolation board 70 is located between the two first clamping portions 575, and when the second clamping portion 61 on the cover 60 is in fit connection with the corresponding first clamping portion 575, the cover 60 can cover the wire harness isolation board 70.
Referring to fig. 3 and 13, in one possible embodiment, the battery cell 10 has a first side 112 and a second side 113 opposite to each other along a third direction C, the number of vertical bars 54 is two, the vertical bar 54 near the first side 112 has a third side 541, the vertical bar 54 near the second side 113 has a fourth side 542, the third side 541 and the fourth side 542 are located on opposite sides of the accommodating space 51 along the third direction C, and in the third direction C, the first side 112 and the third side 541, and the second side 113 and the fourth side 542 have gaps, a third width W3 of the gaps extending along the third direction C, and a third width W3 of the gaps satisfies: w3 is more than or equal to 0.5mm and less than or equal to 0.7mm.
Along the third direction C, the two vertical rods 54 of the bracket 50 are retracted relative to the battery cell 10, a gap is formed, insulating glue can be filled in the gap, the bracket 50 is fixedly connected with the side plate 80 of the battery module 100, the connection strength between the bracket 50 and the side plate 80 of the battery module 100 is improved, and the structural stability of the battery module 100 is improved. In addition, if the third width W3 of the gap extending along the third direction C is smaller than 0.5mm, the space formed by the gap is too small, the volume of the insulating glue filled in the gap is too small, the connection strength between the vertical rod 54 and the side plate 80 is reduced, and the side plate 80 is easy to fall off; if the third width W3 of the gap extending along the third direction C is greater than 0.7mm, the space formed by the gap is too large, and the volume of the insulating glue filled in the gap is too large, so that the weight of the insulating glue is too heavy, the insulating glue is easy to fall off, and the connection strength between the side plate 80 and the vertical rod 54 is further caused. The third width W3 of the gap extending in the third direction C satisfies: w3 is more than or equal to 0.5mm and less than or equal to 0.7mm, the falling phenomenon of insulating glue when filling in the gap is reduced or avoided, the connection strength between the vertical rod 54 and the side plate 80 is improved, and the structural stability of the battery module 100 is improved.
Referring to fig. 6 and 14, in one possible embodiment, the vertical rod 54 has a first projection 545 in the second direction B, the first projection 545 is formed by enclosing a first straight line segment 5451, a second straight line segment 5452 and two arc segments 5453, the first straight line segment 5451 is larger than the second straight line segment 5452, the first straight line segment 5451 and the second straight line segment 5452 are located at opposite sides of the first projection 545 in the third direction C, and the two arc segments 5453 are located at opposite sides of the first projection 545 in the first direction a.
The first straight line segment 5451 is larger than the second straight line segment 5452, that is, the plane where the first straight line segment 5451 is located is larger than the plane where the second straight line segment 5452 is located, wherein the plane where the first straight line segment 5451 is located is connected with the side plate 80 through insulating glue, and therefore the connection strength of the side plate 80 and the vertical rod 54 is improved. The two arc sections 5453 can be used to cooperate with the battery cells 10 mounted on two opposite sides of the bracket 50, so that heat-conducting glue can be filled between the battery cells 10 and the surfaces of the arc sections 5453, and the bracket 50 and the battery cells 10 can be connected in an adhesive manner, and heat dissipation of the battery cells 10 can be realized.
Referring to fig. 10, in one possible embodiment, the bracket 50 further includes a groove 58, where the groove 58 is near the connection between the vertical rod 54 and the second cross rod 53, and the projection of the groove 58 in the second direction B is arc-shaped.
Wherein, the groove 58 is arranged at the joint of the vertical rod 54 and the second cross rod 53, and the groove 58 is closer to the vertical rod 54.
The support 50 is the injection molding, and the projection shape of recess 58 on the second direction B is arc for after the junction drawing of patterns cooling of second horizontal pole 53 and montant 54, local position shrink can not appear, avoids leading to support 50 distortion because of the shrink, promotes the structural strength of support 50.
Referring to fig. 3 and 12, in one possible embodiment, the plurality of battery cells 10 are arranged along the first direction a to form the battery cell group 20, the battery module 100 further includes a side plate 80, the side plate 80 is mounted on two sides of the battery cell group 20 along the third direction C, the side plate 80 is located between the first positioning clamping member 56 and the second positioning clamping member 57, and in the second direction B, the distance between the first positioning clamping member 56 and the second positioning clamping member 57 is greater than the extending height of the side plate 80.
Along the second direction B, the distance between the first positioning clamping piece 56 and the second positioning clamping piece 57 is greater than the extending height of the side plate 80, and after the battery module 100 is assembled with the battery cell 10 and the bracket 50, the assembly gap of the side plate 80 is reserved, so that the side plate 80 is convenient to be adhered to the vertical rod 54 of the bracket 50.
While the foregoing is directed to embodiments of the present application, it will be appreciated by those skilled in the art that changes and modifications may be made without departing from the principles of the application, and such changes and modifications are intended to be included within the scope of the application.