A battery cell comprising a current collector having electrodes and having electrical conductivity and thermal conductivity, and internal and external heat exchangers

Abstract

A battery cell comprising a roll electrode and having at least one boundary of a bent curve for forming a base at at least one end, further comprising a wool cushion bridge, having an electrothermal conductor collector at the battery cell terminal, and comprising an encapsulated assembly sealed in a composite box with a flexible and elastic electrical insulator, the composite box also functioning as an expansion vessel in the event of internal gas generation due to an electrochemical reaction between the anode and the cathode, storing and containing flammable gas inside, being sealed from the outside, the pressure of which is measured in real time by an internal pressure sensor, the internal pressure sensor transmitting its data in real time to the BMS and / or the battery cell controller. The battery cell is provided with a heat exchanger and is assembled into modules and racks with an air or air and liquid hybrid passive or forced cooling system.

Description

Technical Field

[0001] The present invention relates generally to energy batteries and electrical energy storage devices.

Background Art

[0002] The pressure on the current collecting bridge is applied by the flexibility and elasticity of the battery cell case. This flexible body can be disposed at both ends of the battery cell or between the terminals, and this body forms part of the battery cell case structure and is part of the composite case structure. In the battery cell, at least one current collecting plate is welded to the exposed core portion, and this core portion is connected to the conductor of the positive electrode or the negative electrode. This current collecting plate serves to conduct current to the external output terminal. In a high-output battery, it is very important for the current collecting plate to conduct high current stably to the external output terminal. In order to achieve higher conductivity and stable high current, it is advantageous to increase the contact area between the extended current collecting plate and the positive electrode and / or negative electrode core. Thereby, the contact area and the direct contact pressure between the current collecting plate and the electrode are increased, and the weld point can be removed.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Since the contact area of the current collecting plate is limited, the heat generated by the electrode is not transmitted to the terminal or the outside, and heat conduction is hindered.

[0005] However, in a high-capacity laminated battery cell with a large number of winding layers or stacking layers, it is not easy to expand the contact area between the current collector plate and the positive electrode and / or the negative electrode core. As a result, high current and heat cannot be effectively conducted from the electrodes, which may cause overheating.

[0006] The cooling and thermal conductivity required by the electrodes are similarly restricted, which is hindered by the fact that the current collector cannot conduct heat sufficiently through its own structure or the welding points.

Means for Solving the Problems

[0007] The present invention solves the above problems by using a current and heat conducting current collecting bridge device. This device employs a buffer pad composed of wool net or compressed contact sponge, which has a larger surface area than before and can increase the contact area between the current and heat conductor current collecting device and the electrodes (i.e., pole points, positive electrodes, and / or negative electrodes) of the battery cell. This device maintains the contact pressure on the electrodes, expands the contact area through pressure and deformation, and exhibits a similar effect (mirror effect) at the terminals. In the present invention, this device is referred to as an "electric and heat conductor current collecting bridge", which is composed of conductive and thermally conductive materials and uses a buffer pad composed of wool net and compressed sponge inside the battery cell.

[0008] In terms of thermal conductivity, the device of the present invention can ensure the thermal conductivity and stable cooling effect of the electrode surface inside and outside the battery cell by expanding the contact area between the terminal and the electrode.

[0009] Through the present invention, heat is directly discharged from the battery cell from the electrodes through the conductor current collecting bridge. At the same time, the external heat exchanger outside the battery cell ensures uniform, continuous, and rapid cooling, which is realized by the continuous electro-thermal circulation path inside and outside.

Brief Description of the Drawings

[0010]

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Embodiments for Carrying Out the Invention

[0011] In a preferred embodiment of the present invention, the battery cell includes at least one electrode assembly (109 / FIGS. 1 and 110 / FIG. 1, anode and cathode), the electrodes of which are covered with an active composite material (101 / FIG. 1 and 102 / FIG. 1) up to the tab boundary and are symmetrically applied. The tab boundary of the anode (101 / FIG. 1) faces the tab boundary of the cathode (102 / FIG. 1). Based on FIG. 1, the two strip electrodes (103 / FIG. 1 and 104 / FIG. 1) show the partially covered active composite material (108 / FIG. 1) and continue up to the pole point regions (101 / FIG. 1 and 102 / FIG. 1). It also includes an internal separator (106 / FIG. 1) and an external separator (105 / FIG. 1) to form a rechargeable battery cell. The components are wound around an axis (107 / FIG. 1), and there is no active composite material at the ends of the electrodes, which become the pole points (101 / FIG. 1 and 102 / FIG. 1).

[0012] When forming the electrode assembly, after the electrodes (109 / FIG. 1 and 110 / FIG. 1) and the separators (105 / FIG. 1 and 106 / FIG. 1) are laminated, they are wound around the central axis (107 / FIG. 1) to form a central gap (111 / FIG. 1) or a central core having a rectangular and / or elastic shape. This shape is used for compression, but is not limited to a rectangular geometry. In an embodiment, the electrode (103 / FIG. 1) can be an anode and the electrode (104 / FIG. 1) can be a cathode. The separators (105 and / or 106 / FIG. 1) provide electrical insulation to prevent short circuits. The pole points (101 and 102 / FIG. 1) face each other in the axial direction, and the pole point of the anode does not contact the pole point of the cathode.

[0013] In some embodiments, the conductive coating includes the active composite material of the electrode. In some embodiments, the active composite material of the electrode is a cathode active material, and in other embodiments, it is an anode active material.

[0014] The active material can be selected from the following materials: silicon materials (such as metallic silicon and silica), graphite materials, graphene-related materials, hard carbon, soft carbon, carbon nanotubes, porous carbon, conductive carbon, lithium nickel manganese cobalt oxide (NMC), lithium manganese oxide (LMO), lithium cobalt oxide (LCO), lithium titanate oxide, nickel oxide, aluminum cobalt oxide (NCA), layered transition metal oxides (e.g., (LCO), (NMC), (NCA)), manganese spinel oxides (e.g., (LMO) or (LMNO)), olivine, chalcogenide, tavormineral, silicon, silicon oxide, tin, aluminum, tin oxide, manganese oxide, molybdenum oxide, molybdenum disulfide, nickel oxide, copper oxide, and lithium sulfide, or combinations thereof.

[0015] In some embodiments, the first layer also includes a binder for binding the active material to the electrode surface. This binder can be a polymeric material such as polyvinylidene fluoride (PVDF), nitrile rubber (NBR), polyacrylic acid (PAA), or a mixture thereof. This binder provides stable mechanical and chemical properties and ensures that the active composite material adheres firmly to the electrode during the charge and discharge process. Examples of the arrangement of the active composite material include mechanical vapor deposition, electroplating, electrochemical vapor deposition, or any combination of processes known to those skilled in the art. These processes are also applicable to the depositions 108 (FIG. 1) on the electrode substrates 103 (FIG. 1) and 104 (FIG. 1).

[0016] Referring to FIG. 1 and in combination with FIG. 2, the electrode plates 101 (FIG. 2) and 102 (FIG. 2) are bent, deformed, folded, or compressed by a combination of processes known to those skilled in the art, and a base 113 (FIG. 2) is formed at at least one end. This end is on one side of the core 112 (FIG. 2) of the battery cell or is located at the opposite end and is indicated by the edge of the winding spool.

[0017] Before winding, after applying tension, it is recommended to cut or slit the boundary edges of the electrode plates before winding (such as a1, a2, a3, a4, b1, b2, b3 as shown in FIG. 3). This enables uniform winding within the corner regions (A - B - C - D / FIG. 3) of the rectangular axial geometry.

[0018] The cutting process occurs before winding, or it is also possible to cut the anode or cathode electrode strips while applying tension. The distance of the cutting positions (e.g., a1, a2, a3, a4, b1, b2, b3 / FIG. 3) is calculated based on the core radius of the winding axis, and its size is affected by the angular distance between the cuts a1 (FIG. 3) and the distance between the corresponding regions (e.g., region A / FIG. 3). The calculation, adjustment, measurement, cutting, and execution of these sizes can be performed by processes known to those skilled in the art.

[0019] During (or after) the winding process of the battery cell core, the tensioned, cut or scored electrode plates are bent, folded, deformed, or compressed at different angles and radii with respect to the winding axis. The bent electrode plates form a base at at least one end of the core, and electrode plates of the same type are in direct contact from layer to layer, with portions belonging to the same electrode partially or completely overlapping to build electrical and thermal continuity over the entire surface of the base.

[0020] In some embodiments, by bending, deforming, folding, or compressing the sides of the core, a bent, folded, deformed, or compressed portion serving as a base is provided in the electrode plate portion. The portions at the ends of the electrode plates partially or completely overlap through their edges and / or layers (e.g., a1-L1 and b1-L2 in FIG. 3). The cutting and scoring of the electrode plates can be achieved using any process known to those skilled in the art, for example, by performing fiber laser cutting while applying tension.

[0021] The electrodes are wound along an axial geometry to form a winding shape of the initial geometry, but are not limited to this initial geometry. The axial geometry adopts a rectangular shape to improve the volume density of the material and is superior to circular or elliptical geometries. The rectangular shape can fill the ends and corners of modules and battery cell blocks, while circular and elliptical shapes may cause degradation of the electrodes, especially the anode and cathode, in the bending region.

[0022] In a preferred embodiment of the present invention, a rectangular core geometry is adopted and combined with the cuts shown in FIG. 3 to separate the region (A-B-C-D / FIG. 3) and avoid overlap between regions to form a regular base. This base has a large contact surface area and is orderly. Also, this divided folding and overlapping device ensures the regularity of the battery cell core base and the continuity of electrical and thermal conduction.

[0023] As shown in Figure 2, the bridging device (a current collector with electrical conductivity and thermal conductivity) is composed of electrically and thermally conductive materials such as copper nets and copper wires, and functions as a buffer layer inside the battery cell. This device conducts heat efficiently and provides a uniform contact surface area.

[0024] Furthermore, due to the characteristics of the bridging device, it is suitable for forming a structural connection between the electrode plates, improving the thermal characteristics, and enhancing the stability of the entire battery cell. The bridging device can be produced or customized using various manufacturing processes known to those skilled in the art according to the requirements of battery design.

[0025] Referring to Figures 6 and 7, the elastomer 126 (Figure 7) is applied as an axial pressure device 142 (Figure 7) to the assembled parts of the battery cell. This includes the anode and cathode cores, the base, the conductor current collection bridge, the terminals, and the battery outer shell. Its characteristics continuously maintain axial compression and contact between these parts, ensuring the continuity of electrical and thermal flow inside the battery and between its various elements, while not interfering with the surface and / or shape.

[0026] Referring to Figures 1 to 7 and 8, the battery cell 128 (Figure 8) can be assembled as a set, module, block, and / or pack. Outside the battery outer shell, a heat exchange device composed of a heat-conducting material, a wool net, and a compressed sponge pad is attached, fixed between the battery cell outer shells 128 (Figure 8), and in contact with the outer shell wall. This enables the cooling of the battery. These heat exchange devices 119 (Figure 8) can partially or completely enclose the battery cell and cover the battery in the horizontal or vertical direction. There is no limitation in the covering direction, and as long as it enters the cooling flow, it constitutes an important component of the present invention.

[0027] Referring to FIGS. 8 and 9, the heat exchanger 119 (FIG. 9) is applied to the prismatic battery cell 129 (FIG. 9), which is an important component of the present invention. Modules and blocks can be assembled by various combination methods known to those skilled in the art. The prismatic battery cell is cooled by a heat exchanger embedded between the prismatic batteries, ensuring contact with the battery surface and filling the space between the cells. Even if volume changes occur in the space between the cells, the heat exchanger 119 (FIG. 9) ensures the continuity of the thermal conductivity and the retention of the heat flow chain, and operates in cooperation with a passive cooling system or a forced cooling system.

[0028] Referring to FIGS. 8 and 10, the heat exchanger 119 (FIG. 10) is also applied to the soft pouch type battery cell 130 (FIG. 10). The soft pouch type battery cell is cooled through a heat exchanger inserted between the cells. This device contacts the surface of the battery and fills the gap. Even under conditions where the volume changes, these heat exchangers ensure the continuity of heat conduction and can perform cooling using a passive cooling, forced cooling, or gas-liquid mixed cooling system.

[0029] The battery module (FIG. 11) provided by the present invention includes at least two battery cells and has a continuous heat flow chain (FIG. 15). For example, in a horizontal view, the module can adopt a gas-liquid mixed cooling method. The heat generated in the battery cell 131 (FIG. 11) is absorbed by the heat exchanger 119 (FIG. 11) in contact with the battery and is guided to the cooling radiator 132 (FIG. 11) through a passive or forced cooling flow. This radiator discharges heat through a liquid cooling system to complete the cooling of the module assembly 133 (FIG. 11).

[0030] The cooling flow of the module adopts a gas or gas-liquid mixed cooling method, and forms a closed-loop or semi-closed-loop cooling circuit by forced cooling with the front fan 134 (FIG. 11). The cooling flow circulates between the battery cells, in the radiator and within the module to ensure the heat exchange efficiency of the entire system.

[0031] Referring to FIGS. 11, 12 and 13, the modules of the present invention can be stacked or assembled in a stack (FIG. 13) to form a power storage device 144 (FIG. 13). The modules can have an independent air-liquid mixing cooling system or can be connected to a central liquid cooling circuit. In the central liquid cooling circuit, coolant is supplied to a radiator via a pump and pipes (139 and 140 in FIG. 13). These modules can be attached and removed in a drawer-type format without interfering with physical, mechanical, or thermal performance.

[0032] The battery modules or blocks (FIG. 13) can include an independent forced cooling system, for example, a front fan 134, a side radiator 132, an intake area 137, and an exhaust area 138. The heat exchanger is arranged between batteries or within the module to ensure the heat exchange performance of the module in a closed-loop or semi-closed-loop cooling circuit.

[0033] The closed-loop cooling system is one of the overall components of the present invention. The rack cooling system (144 / FIG. 13) shown in FIG. 13 usually employs liquid cooling and is connected to the rack (144 / FIG. 13) by pipes (139 / FIG. 13 and 140 / FIG. 13) that supply coolant via a pump. This system supplies coolant to radiators (132 / FIG. 13) on both sides of the module or radiators (144 / FIG. 13) on both sides of the rack.

[0034] The module assembly (133 / FIG. 13) shown in FIG. 13 is composed of modules having a forced cooling and / or hybrid cooling system including a front fan (134 / FIG. 13), a side radiator (132 / FIG. 13), an intake zone (137 / FIG. 13), an exhaust zone (138 / FIG. 13), and a heat exchanger arranged between battery cells within the module.

[0035] The battery module or block (133 / Figure 13) is removable and designed in a drawer-type format, and can be inserted into and removed from the rack. This fixes the radiator on the module side without causing physical, mechanical, or thermodynamic collisions with the liquid cooling circuit, and separates the liquid cooling circuit that provides cooling to the equipment of the power storage device from the forced air cooling flow of the module.

[0036] The continuous flow electric chain shown in Figure 14 is not affected by the areas of materials, contacts, welds, or contact surfaces, and is characterized by being reversible and bidirectional. Starting from the electrode (104 / Figure 1), it reaches the bottom of the battery core (114 / Figure 2) through the terminal (102 / Figure 1), and is connected to the electrothermal conductor collection bridge (woolen net and compressed sponge pad inside the battery cell) (116 / Figure 2) composed of conductive and thermally conductive materials via the terminal (102 / Figure 2). When applicable, it is connected to the CT current reversal contactor (123 / Figure 5), and further connected to the external terminal of the battery enclosure (118 / Figure 2 and / or 118 / Figure 4). This component constitutes a continuous current flow and conductive chain, is part of the overall components of the present invention, and can be realized by any combination process known to those skilled in the art.

[0037] The continuous flow heat chain shown in FIG. 15 is similarly not affected by the areas of materials, contacts, welds, or contact surfaces, and is reversible and bidirectional. Starting from the electrode (104 / FIG. 1), it reaches the bottom of the battery core (114 / FIG. 2) through the terminal (102 / FIG. 1), and is connected to a heat and electrical conductor collecting bridge (a wool mesh and a compressed sponge pad inside the battery cell) (116 / FIG. 2) composed of conductive and thermally conductive materials via the terminal (102 / FIG. 2). If applicable, it is connected to a CT current reversal contactor (123 / FIG. 5), and further connected to the external terminal of the battery enclosure (118 / FIG. 2 and / or 118 / FIG. 4). Then, it reaches a central liquid cooling system (139-140 / FIG. 13) via a heat exchanger composed of a thermally conductive material (a wool mesh and a compressed sponge pad outside the battery) (119 / FIG. 4), a forced liquid cooling radiator (132 / FIG. 11, 132 / FIG. 12, and 132 / FIG. 13), and a mixed gas-liquid cooling flow (136 / FIG. 11), and forced circulation is performed by a pump. This component constitutes a continuous heat flow and heat conduction chain, is part of the overall components of the present invention, and can be realized by any combination process known to those skilled in the art.

Claims

1. A battery cell comprising a battery cell core (112) formed by at least one assembly of electrodes, the electrodes consisting of an anode and a cathode, and their poles (101) / (102) being covered with an active composite material in a mirror arrangement up to the edges, the edge of the anode pole facing the edge of the cathode pole, and the edge of at least one pole being bent (101) and / or (102) to form a base part (113) and / or (114) at at least one end, the core (112) extending into at least one electrical and thermal current collector bridge (115) and / or (116), characterized in that the improvement of the current collector bridge consists of a wool mesh. Further, it has the following features: the electrical induction for each individual mesh is multiplied with respect to the wool mesh, the compression and contact cushion of the wool mesh function as a contact surface with the terminal (118) and at least one base part (113) and / or (114), and it has the feature that welding to the base part (113 / 114) and the terminal (118) of the battery cell box (129) is not required, and the battery cell box is a battery cell box not limited to square (129), (128), (131), etc.

2. A battery cell according to Claim 1, further comprising an anode and a cathode electrode wound around a central axis having a square geometric shape, the shape being composed of a region (A - B - C - D), the strip-cut end of at least one electrode being located at the corner edge between (A - B - C - D), the end folding back, bending, and overlapping the base layers (a1 - L1) and (b1 - L2) (L1 - L2) / (L3 - L4), being pre-cut (a1, a2, a3, a4, b1, b2, b3) before winding, and being flattened in the region (117) between the edges of the base part.

3. Regarding the battery cell according to claim 1, the battery cell box further comprises a flexible and / or elastic trampet (126) as an internal expansion vessel device (143) between the terminals, the terminals (118) are configured in a mirror or opposed arrangement, the box functions as a sealed internal volume exchanger, the elastic trampet (126) maintains an internal elastic axial compression (142), welding of the bridges (115)(116) to the terminals (118) and / or the terminals (125) / (127) is unnecessary, and it is characterized by comprising an electrical and / or thermal insulator. The box is not limited to a square type (129), (128), (131) or any battery cell box according to claim 1.

4. Regarding the battery cell according to claim 1, the battery cell core (112) further comprises an internal pressure sensor, a pressure transmitter, and / or a pressure transducer (141), the sensor is connected to the BMS and / or the MCU controller of the battery cell by "input" and "output", and it is characterized by transmitting the pressure and generation of combustible gas in real time.

5. A battery cell according to claim 1, further comprising a heat exchange device (119) made of a heat conductor, a cotton wool mesh pad, and / or a compressed sponge of a heat conductive material outside the battery cell, the heat exchange device is connected to the outside of the pouch type battery (130) or the square battery cell (129) through the surface area of the wool mesh, contacts and is fixed to the wall of at least one battery cell box, and conducts and exchanges the continuous heat flow from the internal anode / cathode core to an external passive or forced cooling system.

6. A battery cell module including at least two battery cells according to any one of claims 1 to 5, the module further comprises a heat exchanger (119) assembly according to claim 5, the heat exchanger is made of a heat conductor, a cotton wool mesh pad, and / or a compressed sponge of a heat conductive material, and is arranged to fill the gaps between and / or around the battery cells (128), (129), (130), and continuously transmits the heat flow of the battery cell assembly to a passive or active cooling system without limitation of surface, volume, and shape.

7. A battery cell module assembled from at least two battery cells according to any one of claims 5 to 6, the module comprising: - a front fan (134), an area (138) for sending cold air currents above and below the battery cells (131), and a side intake area (137); - holes provided above and below the battery cell module (133) that guide cold air currents to the heat exchanger cooling areas of the battery cells, block the cold air currents to increase the pressure in the sending area (138), achieve uniform steady cooling, and distribute proportional cold air according to the position and arrangement of the heat exchangers (119) of each rectangular battery cell (128), (129), (131); - a heat flow path to the intake area (137) that passes between the heat exchangers (119) and between the battery cells, is discharged via a liquid cooling radiator (132), and the radiator is arranged on the side or end of the battery cell module.

8. A battery cell module (133) by a cooling chain method including at least two battery cell assemblies comprising the rectangular battery cells (128), (129), (131) or pouch-type battery cells (130) according to claim 1 and heat exchangers (119), the module distributing the cooling air pressurized by a fan (134) from a sending area (138) through an aligned hole (135) to the heat exchanger (119), sucking the cooling air from a water-cooled radiator (132) through an intake area (137), and the radiator discharging heat to a separated water-cooling system (139) and (140) outside the battery cell module.

9. An assembly of a battery cell module according to any one of claims 6 to 8, forming a rack (144) with a water-cooled radiator network (132) and a reciprocating water path (139) / (140), the water-cooling system belonging to the rack, the air-cooling by a fan (134) belonging to each module (133), the attachment and detachment of the module having no influence on the water path, and being a hybrid method that operates in cooperation while being a separated circuit with different cooling water and air-cooling.

10. A rack for a power storage device assembled with at least two modules according to any one of claims 6 to 9, the rack comprising a hybrid air-cooling / liquid-cooling system, having a water-cooled radiator (132) disposed on a side surface, circulating a liquid with a central pump, and the module (133) being detachable in a drawer type and exchangeable without technical interference with a liquid cooling circuit (139-140).

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