Battery Module End Plate Thickness Layout for Weight-Strength Balance

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

The challenge is to reduce the weight of the end plate in battery modules while maintaining sufficient structural strength to improve energy density without compromising the integrity of the battery module.

Innovation Solution

The end plate is designed with varying thicknesses, featuring a thicker first mating part and a thinner second mating part, along with a preset gap between the end plate and the mounting beam, allowing for efficient assembly and expansion without excessive restraint, and using cable ties with different tensile strengths to distribute stress effectively.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Weight of moving object

If the thickness of the end plate is reduced to decrease weight, then the weight of the end plate is reduced, but the structural strength is compromised

Engineering Contradiction:
Improveweight of end plateVSAvoidstructural strength
Core Design Contradiction:
Weight of moving objectVSStrength

Solution Approach 1:

The end plate is designed with non-uniform thickness distribution, featuring a first mating part with greater thickness for enhanced strength and a second mating part with smaller thickness for weight reduction. This local quality variation allows different regions of the same component to serve different functional requirements - the thicker region provides structural integrity while the thinner region reduces overall weight.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The end plate is segmented into multiple regions with different thickness characteristics - a first mating part with larger thickness and a second mating part with smaller thickness. This segmentation allows the component to optimize both strength and weight by assigning different thickness values to different functional zones within the same end plate structure.

Inventive Principle:
Principle #1Segmentation

2Weight of moving object

If the end plate is made thinner to reduce weight, then the weight is reduced, but the reliability of the battery module is compromised

Engineering Contradiction:
Improveweight of end plateVSAvoidintegrity of battery module
Core Design Contradiction:
Weight of moving objectVSReliability

Solution Approach 1:

The end plate employs local quality variation with a thicker first mating part that provides enhanced reliability for critical structural functions, while the thinner second mating part reduces weight in less critical areas. This localized thickness optimization ensures that reliability is maintained where needed without sacrificing weight reduction benefits.

Inventive Principle:
Principle #3Local quality

3Reliability

If cable ties with high tensile strength are used to ensure structural integrity, then the reliability is improved, but the weight of the battery module increases

Engineering Contradiction:
Improvestructural integrityVSAvoidweight of battery module
Core Design Contradiction:
ReliabilityVSWeight of moving object

Solution Approach 1:

The cable ties are designed with varying tensile strength parameters along their length, with the first cable tie having greater tensile strength for critical structural support and the second cable tie having smaller tensile strength for less critical functions. This parameter variation allows the system to achieve necessary reliability while minimizing the weight contribution of the cable tie assembly.

Inventive Principle:
Principle #35Parameter changes

4Ease of manufacture

If the end plate is designed with uniform thickness to simplify manufacturing, then the ease of manufacture is improved, but the energy density is reduced due to excessive weight

Engineering Contradiction:
Improvemanufacturing simplicityVSAvoidenergy density
Core Design Contradiction:
Ease of manufactureVSQuantity of substance

Solution Approach 1:

The end plate is designed with local quality variation where the first mating part has greater thickness and the second mating part has smaller thickness. This non-uniform design optimizes the balance between manufacturing complexity and energy density by concentrating material only where structurally necessary, thereby improving energy density without making manufacturing excessively difficult.

Inventive Principle:
Principle #3Local quality

Data Source

PatentEP3879621B1Battery pack and apparatus
Publication Date: 2024.11.13 CONTEMPORARY AMPEREX TECHNOLOGY (HONG KONG) LIMITED
  • EP3879621B1 patent drawingFigure 1~2
  • EP3879621B1 patent drawingFigure 3~4
  • EP3879621B1 patent drawingFigure 5~6

AI summary

The present application relates to a battery module, a battery pack and an apparatus. The battery module includes: a battery cell arrangement structure including a plurality of battery cells stacked on each other; and an end plate, the end plate being located at an end part of the battery cell arrangement structure in a length direction, and the end plate including a first mating part and a second mating part; where the second mating part is located below the first mating part in a height direction of the battery module, and a thickness of the second mating part is smaller than a thickness of the first mating part. The thicknesses of the first mating part and the second mating part of the end plate are different, so that the end plate is a structure without completely the same thickness at each position, thereby reducing a weight of the end plate and improving energy density of the battery module while ensuring that the end plate has higher strength. Meanwhile, when a thickness of the end plate is not completely the same at each position and the battery module is mounted to a box, mating of the end plate with another component in the box could be easy to be achieved, and assembly efficiency is improved.