Battery Cell Shell Welding Structure for Crack Resistance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The shell of battery cells is prone to breakage due to internal expansion or external stress, compromising the reliability of the battery cell.
Innovation Solution
A battery cell design where the shell includes a first plate portion thicker than a second plate portion, with welding pores located in the first plate portion to reduce stress on the second plate portion, thereby enhancing structural reliability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the shell uses uniform thickness for both plate portions, then manufacturing is simpler, but the second plate portion is prone to cracking and breakage due to welding pores
Solution Approach 1:
The shell employs non-uniform thickness distribution where the first plate portion has greater thickness than the second plate portion. This local quality differentiation allows the first plate portion to bear the welding pores while maintaining sufficient strength, preventing cracking in the thinner second plate portion that accommodates the electrode assembly.
Solution Approach 2:
The shell is divided into two distinct plate portions with different thickness characteristics. The first plate portion (greater thickness) is positioned to contain welding pores, while the second plate portion (smaller thickness) maintains structural integrity for electrode accommodation, thereby segmenting the functional requirements of the shell.
2Ease of manufacture
If welding pores are located in the second plate portion, then welding process is easier, but the strength of the second plate portion is reduced causing cracking risk
Solution Approach 1:
The welding pores are extracted from the second plate portion and relocated to the first plate portion. This extraction removes the harmful effect of welding pores from the strength-critical second plate portion, allowing easier welding execution while preserving the strength of the second plate portion for maintaining shell integrity.
3Reliability
If the first plate portion has greater thickness, then it can protect against cracking, but the overall shell weight increases
Solution Approach 1:
Instead of uniformly increasing the thickness of the entire shell, the design applies local quality enhancement only where needed - the first plate portion has greater thickness to provide crack resistance and accommodate welding pores, while the second plate portion maintains smaller thickness to minimize weight, achieving optimal strength-to-weight ratio.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The design effectively reduces the risk of cracking and breakage of the battery cell shell, improving its reliability and service life by distributing stress more evenly.
Implementation Method 1
The first plate portion is welded to the second plate portion by laser radiation to form a molten pool structure that penetrates deep into the first plate portion
Data Source
AI summary
This application provides a battery cell, a battery, an electrical device, and a method for preparing a battery cell. The battery cell includes a shell and an electrode assembly. The shell provides an accommodation space. The shell includes a first plate portion and a second plate portion. The first plate portion is welded to the second plate portion to form a molten pool structure and welding pores located in the molten pool structure. The electrode assembly is accommodated in the accommodation space. A thickness of the first plate portion is greater than a thickness of the second plate portion. At least a part of the welding pores are located in the first plate portion.