Analysis of CATL Wave Battery Cell Structure Patents

1. Key Structural Design Points

The disclosed battery cell is composed of the following main elements:

• Housing: A shell with a containment cavity for accommodating the bare cell core.

• Bare Cell Core: Positioned within the cavity, featuring multiple electrode tabs aligned along a first direction.

• Terminal Posts: Mounted on the end cap of the housing.

• Adapter Plates: Serving as conductive interfaces that connect the electrode tabs to the terminal posts.

Critical design characteristics:

• Connection Points:

  • Position 1: Defined at the interface between electrode tabs and adapter plates.

  • Position 2: Defined at the interface between terminal posts and adapter plates.

• Wave-shaped End Cap & Housing:

  • Incorporates alternating first covers and second covers.

  • The first cover is arranged closer to the bare cell core, forming a stepped or wave-like configuration.

  • This overlap between terminal and tab spatial regions reduces cell length along the second direction, thereby improving volumetric energy density.

2. Structural Optimization Aspects

• Tab Arrangement: Tabs are positioned opposite to their adjacent terminal posts, increasing spacing between positive and negative electrodes and minimizing short-circuit risk.

• End Cap Design:

  • Divided into first covers (for terminal mounting) and second covers (for tab accommodation).

  • The first cover is placed closer to the cell body, maximizing spatial efficiency.

• Adapter Plate Design:

  • Incorporates a first connection plate with adapter slots and multiple second connection plates.

  • This configuration reduces conductive material usage and manufacturing costs.

• Terminal–Adapter Connection:

  • Terminals are inserted into adapter slots and welded.

  • This method lowers structural height while improving electrical stability and mechanical strength.

3. Technical Challenges and Potential Risks

3.1 Structural Complexity

• The wave-shaped end cap requires highly accurate stamping or injection molding.

• Stress concentration may occur at curved junctions between the first and second covers, affecting sealing performance.

• Assembly demands strict tolerance control, raising production costs and reducing manufacturing yield compared to conventional flat designs.

3.2 Sealing Reliability

• Multiple grooves and seams increase sealing difficulty.

• Height differences complicate vertical welding, making side welding a more suitable option.

• Risks include electrolyte leakage or external contaminant ingress, which compromise safety and lifespan.

3.3 Thermal Management

• Spatial overlap between terminals and tabs creates localized heat concentration.

• Dissipation paths become more complex, potentially impairing thermal stability under high-load conditions.

3.4 Adapter Plate Integrity

• Split-plate structures may introduce weak points at connection interfaces.

• Long-term vibration or impact may cause micro-motion wear, raising contact resistance and lowering reliability.

3.5 Terminal–Slot Engagement

• Although slots enhance connection, precision machining is essential.

• Insufficient accuracy or material fatigue could lead to poor electrical contact, increased impedance, or terminal detachment.

4. Claim Section (Simplified Interpretation)

1. A battery cell comprising a housing, a bare cell core with electrode tabs, terminal posts, and adapter plates, where Position 2 (terminal–adapter connection) is closer to the cell body than Position 1 (tab–adapter connection) along the second direction.

2. Tabs are arranged opposite to adjacent terminal posts to increase spacing.

3. The housing incorporates alternating first and second covers, enabling efficient terminal and tab accommodation.

4. Distance relationships between covers and terminals ensure spatial compactness.

5. Multiple bare cell cores can be arranged in the third direction, with first and second connection plates forming the adapter structure.

6. A battery pack comprising multiple such battery cells.

7. An electrical or energy storage device comprising said battery pack.

5. Specification Section

5.1 Description of Embodiment

• Spatial Overlap Strategy: Positioning Position 2 closer to the cell body allows terminal space and tab space to overlap, reducing cell length in the second direction.

• Safety Enhancement: By locating tabs opposite terminal posts, inter-tab spacing is increased, lowering the likelihood of internal short circuits.

• Wave-shaped End Cap: Alternating covers provide space-saving design while preventing terminal protrusion, maximizing usable volume.

• Shell Optimization: Grooves on side plates accommodate first covers, reducing material usage and improving sealing compatibility.

• Adapter Optimization: Multiple second plates reduce copper/aluminum consumption, while adapter slots improve weld stability and structural compactness.

5.2 Implementation Methods

• Structural diagrams show several wave-shaped end cap configurations (single-first-cover, dual-first-cover, or alternating patterns).

• Cross-sectional views demonstrate relative distances and overlaps between terminals, tabs, and covers.

• Adapter plate drawings illustrate slot-based welding design.

• Dimensional notations define key distance relationships to ensure compactness and reliability.