EP-4738535-A1 - BATTERY PACK, VEHICLE, AND ASSEMBLING PROCESS OF BATTERY PACK

EP4738535A1EP 4738535 A1EP4738535 A1EP 4738535A1EP-4738535-A1

Abstract

A battery pack includes a bottom cell holder (0520) with receiving structures that provide lateral and vertical forces to hold the battery cells (0020). The bottom cell holder (0520) includes a layer of lateral stopping structure (0521), a layer of vertical stopping structure (0522) and a plurality of venting structures (0523). The lateral stopping structure (0521) is configured to receive the battery cells (0020). The vertical stopping structure (0522) is configured for supporting weight of the battery cells (0020). The vertical stopping structure (0522) has multiple lateral channels (0526), which divide the vertical stopping structure (0522) into discrete islands. When a thermal event causes the battery cell (0020) to release gas from its bottom, the gas passes the lateral channels (0026) between the discrete islands and then enters the through hole of the venting structure (0523) and move vertically towards top end of the venting structure (0523).

Inventors

LIN, YU-CHUNG
CHI, YU-SHUN
DAI, SHANG-CHIH
LIAO, TZU-WEN
Chuang, Chin-Yao
TU, KAI-HSIANG
Tang, Tzu-Te
HUANG, LI-HSIANG
WU, I-Jung

Assignees

Xing Power Inc.

Dates

Publication Date: 20260506
Application Date: 20251104

Claims (15)

A battery pack characterized by the battery pack comprising: at least one battery cell assembly (BCA) (0010) comprising: a plurality of battery cells (BCs) (0020); at least one cell holder (0510, 0520) configured to limit the position of the battery cells (0020); and at least one battery-cell-connecting member (BCCM) (0026) that is an electrical conductor configured to connect to electrodes of the battery cells (0020); a liquid-tight enclosure (3080) configured to limit movement of a thermal-management liquid, comprising: a front side wall (3091), a left side wall (3094), a right side wall (3093), a rear side wall (3092), a bottom wall (3100) and a top wall (3110) that are integrated as the liquid-tight enclosure (3080), and combined to define a space (3120) for accommodating the battery cells (0020), the at least one cell holder (0510, 0520), the at least one BCCM (0026) and the thermal-management liquid; a coolant inlet (3095) and a coolant outlet (3096) respectively installed on the right side wall (3093) and the left side wall (3094), wherein the coolant inlet (3095) and the coolant outlet (3096) are configured to be the interface of inputting and outputting the thermal management liquid; at least one high-voltage connector (3097) installed on the front side wall (3091) for electrically connect to an electrical equipment; and at least one busbar (3181, 3182) being connected to the high-voltage connector (3097) and the BCCM (0026), so as to provide the high-voltage electrical connection between the BCA (0010) and the electrical equipment; and wherein the enclosure (3080) is configured to be welded, adhesive bound, or bolted connected with the electrical equipment; and a battery management system (3060) comprising at least one cell monitoring circuit (CMC) (3061); and wherein one BCA (0010) is monitored by one CMC (3061); and wherein an external connecting interface (3190) of the CMC (3061) is assembled to the enclosure (3080), which the external connecting interface (3190) is configured to connect a low-voltage connector of a downstream signal circuit.
The battery pack of claim 1 further characterized in that : the enclosure (3080) comprises a signal opening structure (3081); and wherein the signal opening structure (3081) is a through hole extended from the inner-surface of the front side wall (3091), to the outer-surface of the front side wall (3091), such a through hole provides a channel to accommodate the signal communication interface.
The battery pack of claim 2 further characterized in that : the through hole comprises a cylindrical-channel structure (3082) and a square-channel structure (3083); and wherein the cylindrical-channel structure (3082) provides a trough-hole extended from the inner surface of the side wall (3090) to a middle section in the front side wall (3091), such a through-hole has a round-edged-inner opening facing the BCA-space (3120), and a round-edged outer-opening facing the external space of the enclosure (3080).
The battery pack of claim 1 further characterized in that : the battery pack comprises a holder connecting member (3140); and the cell holder comprises a bottom cell holder (0520); and wherein the bottom cell holder (0520) is attached to a surface of the bottom wall (3100); wherein the bottom cell holder (0520) has a protrusion (0528), the holder connecting member (3140) has a positioning hole (3141), the protrusion (0528) is inserted into the positioning hole (3141) to position the holder connecting member (3140) on the bottom cell holder (0520).
The battery pack of claim 4 further characterized in that : the holder connecting member (3140) comprises a plurality of fence structures (3142) that define a lateral channel for fluid to pass by spacing between the fence structures (3142).
The battery pack of claim 1 further characterized in that : the cell holder comprises a bottom cell holder (0520); and wherein the bottom cell holder (0520) is attached to a surface of the bottom wall (3100), the bottom cell holder (0520) comprises receiving structures that provide lateral and vertical forces to hold the battery cells (0020), the bottom cell holder (0520) comprising: a layer of lateral stopping structure (0521), the lateral stopping structure (0521) being planar structure with receiving holes (0525), the receiving holes (0525) penetrating upper and lower surfaces of the bottom cell holder (0520) and being configured to receive the battery cells (0020); a layer of vertical stopping structure (0522) attached at bottom of the lateral stopping structure (0521) and configured for supporting weight of the battery cells (0020), the vertical stopping structure (0522) having multiple lateral channels (0526), which divide the vertical stopping structure (0522) into discrete islands, wherein between those discrete islands, the lateral channels (0526) forming gaps between the bottom cell holder (0520) and the bottom wall (3100), the lateral channels (0526) distributed laterally being formed to allow liquid or gas released from bottom of the battery cells (0020) to pass; and a plurality of venting structures (0523) located above the lateral channels (0526) of the vertical stopping structure (0522), comprising through holes that extended from very lower end of the lateral stopping structure (0521) to very top end of the venting structures (0523), thereby allowing gas or liquid flow vertically through the through holes, the lateral channels (0526) being fluidically connected to the venting structures (0523) or the vertical fluid channel structures (0524); wherein, when a thermal event causes the battery cell (0020) to release gas from its bottom, the gas passes the lateral channels (0526) between the discrete islands and then enters the through hole of the venting structure (0523) and move vertically towards top end of the venting structure (0523).
The battery pack of claim 6 further characterized in that : the bottom cell holder (0520) further comprises a connecting structure (0527) and a plurality of vertical fluid channel structures (0524) located at opposite sides of the bottom cell holder (0520); and wherein the lateral channels (0526) are fluidically connected to the vertical fluid channel structures (0524); and wherein the bottom cell holder (0520) has the connecting structure (0527) for connecting to other bottom cell holders (0520).
The battery pack of claim 6 further characterized in that : a horizontal projection area of the vertical stopping structure (0522) is smaller than a horizontal projection area of the bottom cell holder (0520).
The battery pack of claim 1 further characterized in that : the BCCM (0026) electrically connects a plurality of BCs (0020) in parallel as a plurality of in-parallel connected groups of BCs (0020), and connects the plurality of those in-parallel connected groups of BCs (0020) in series with at least one adjacent BC (0020).
The battery pack of claim 1 further characterized in that : the right side wall (3093) comprises a first internal passage (3098) that is a through hole with a first end that fluidically connected to the coolant inlet (3095)and a second end that fluidically connected to the BCA-space (3120); and the left side wall (3094) comprises a second internal passage (3098) that is a through hole with a first end that fluidically connected to the coolant outlet (3096) and a second end that fluidically connected to the BCA-space (3120).
The battery pack of claim 10 further characterized in that : each the right side wall (3093) and the left side wall (3094) further comprises at least one passage interface structure that is configured as a fluidical interface between the internal passage and the BCA-space (3120); wherein the at least one passage interface structure comprises multiple vertical protrusions (3099) extended from the inner side of the underlying right-side wall (3093) or the left side wall (3094); and wherein a space between two adjacent vertical protrusions (3099) function as a fluid channel for the fluid to flow between the internal passage (3098) and the BCA-space (3120).
A vehicle (3010) characterized by the vehicle (3010) comprising: a chassis (3020); and a battery system (3030) comprising at least one battery pack of claim 1 integrated to the chassis (3020).
The vehicle (3010) of claim 12 further characterized in that : the battery system (3030) comprises at least one battery cell assembly (0010), a battery management system (3060) and a thermal management system (3070); and the at least one battery cell assembly (0010) are formed by the battery cells (0020) electrically connected by the at least one BCCM (0026).
An assembling process of a battery pack characterized by the assembling process comprising: assembling a plurality of side walls (3090) of an enclosure (3080), wherein the side walls (3090) comprises a front side wall (3091), a rear side wall (3092), a right side wall (3093) and a left side wall (3094), and high-voltage connectors (3097) and signal interface circuit boards (3190) are installed on the front side wall (3091); installing a coolant inlet (3095) and a coolant outlet (3096) on the right side wall (3093) and the left side wall (3094) respectively; placing a bottom cell holder (0520) into the enclosure (3080); assembling a holder connecting member (3140) to the bottom cell holder (0520); assembling two barriers (3150) to the right side wall (3093) and the left side wall (3094) respectively; assembling a plurality of battery cells (0020) to the bottom cell holder (0520) within the enclosure (3080); connecting a part of the high-voltage connector (3097) inside the enclosure (3080) to a contactor (3160) within the enclosure (3080); assembling a plurality of connecting rods (3170) to a plurality of insertion holes (0529) of the bottom cell holder (0520), wherein the connecting rods (3170) are located between the battery cells (0020) and protrude from above the battery cells (0020); assembling a top cell holder (0510) to the connecting rods (3170) and above the battery cells (0020); filling an interstitial material into the enclosure (3080) to fix the battery cells (0020); disposing a plurality of battery-cell-connecting members (0026) on the top cell holder (0510) and assembling the battery-cell-connecting members (0026) to the battery cells (0020); sequentially installing two busbars (3181, 3182) into the enclosure (3080), so as to provide high-voltage electrical connection from inside to outside of the battery pack; installing a battery management system (3060) into the enclosure (3080), so as to provide signal connection from inside to outside of the battery pack; installing circuit layout of a temperature sensor; installing a bottom wall (3100) on a bottom of the enclosure (3080); and installing a top wall (3110) on a top of the enclosure (3080) and installing a plurality of signal outlets (3200) on the top wall (3110).
The assembling process of claim 14 further characterized in that : the battery cells (0020) are electrically connected by the battery-cell-connecting members (0026) to form a plurality of battery cell assemblies (0010) electrically connected in series; and a plurality of battery-cell-assembly-electrodes (0031) are respectively assembled to the right side wall (3093) and the left side wall (3094) to connect the battery cell assemblies (0010) in series, so as to form a battery system (3030).

Description

Field of the Invention The present invention relates to the integration of battery cells that is configured as a device that can both store and release electric energy, particularly a machine that is assembled from battery cells wherein all the battery cells are immersed in thermal-management liquid while operating. Background of the Invention Electrical energy is widely used to power modern machines. At various stages of the life cycle of electric energy, such as generation, distribution, and consumption, the temporary storage and subsequent release of energy as needed are both significant and necessary. A rechargeable battery cell is a device that stores electrical energy by converting it into chemical energy (i.e., during the charging process) and then reconverting it into electrical energy (i.e., during the discharging process). Depending on the application, battery cells are integrated through a variety of methods to meet the required electrical performance parameters. The integration of battery cells, or in other words, a battery cell assembly, is typically considered a subsystem of an electric equipment. In this disclosure, the phrase "electric equipment" may be referred to an electrically powered machinery, a vehicle that has an electric motor as a prime mover, or an electric energy storage system that is connected electrically to a grid or power plant, or a computing machine (e.g. a server with IT gears, circuit boards, and/or integrated circuit component that are configured to perform computational or information processing functions). Thus, it is also critical to consider the integration between the battery cell assemblies and the electrical equipment. Furthermore, it is well-known that integrating battery cells involves incorporating thermal management systems and battery management systems. With the above-mentioned design considerations, optimizing the integration of battery cells presents significant challenges. Summary of the Invention I. Problems Addressed Optimizing the integration of battery cells requires simultaneously managing thermal performance, electrical interfaces, mechanical stack-up, and manufacturability. In immersion systems, the thermal-management liquid is configured to directly contact the battery cells while its movement is limited so modules can be stacked and sealed into a liquid-tight battery-pack enclosure. A coolant inlet and a coolant outlet may be installed on at least one side wall of the enclosure and configured to be the interface of inputting and outputting the thermal management liquid to the thermal management system. A battery cell assembly may comprise cell monitoring circuits, temperature sensors, and voltage sensors to facilitate battery management functions. The battery cell assembly comprises a bottom cell holder attached firmly to the bottom wall of the enclosure. The bottom cell holder comprises receiving structures that provide lateral and vertical forces to hold the battery cells. The bottom cell holder may be a rectangular plate and comprise a layer of lateral stopping structure, a layer of vertical stopping structure and a plurality of venting structures. The battery cells can be positioned on the bottom cell holder by the lateral stopping structure and the vertical stopping structure. The venting structures may include through holes that extended from the very lower end of the lateral stopping structure to the very top end of the venting structures, thereby allowing the gas or liquid flow vertically through the through holes. The bottom cell holder may have a connecting structure for connecting to other bottom cell holders. II. Technical Effects Immersion cooling maintains battery-cell temperature within a predetermined range and can mitigate combustion. The receiving structures of the bottom cell holder can provide lateral and vertical forces to hold the battery cells. The battery cells can be positioned on the bottom cell holder by the lateral stopping structure and the vertical stopping structure. The inner side walls of the receiving holes limit the lateral movement of the battery cells. The vertical stopping structure protrudes inward in the radial direction of the receiving hole to support the battery cells, such that the vertical stopping structure limits the downward vertical movement of the battery cells. The through holes of venting structures allow the gas or liquid flow to vertically pass through. The vertical stopping structures may have multiple lateral channels, which divide the vertical stopping structures into discrete islands. Between those discrete islands, the channels distributed laterally are formed to allow liquid or gas released from the bottom of the battery cells to pass. III. Dependencies and Problem-Domain Containment Root system architecture → battery pack layouts, sealing, manufacturing: Claim 1 establishes battery cell assemblies, the liquid-tight battery-pack enclosure configured to be integrated with an electrical e