Battery Elastic Contact Structure to Prevent Internal Short Circuits
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current electrochemical devices, such as lithium-ion batteries, face challenges in achieving high energy density and safety due to issues like internal short circuits caused by weld burrs or electrode post piercing the separator, which complicates the manufacturing process and increases costs.
Innovation Solution
A battery design featuring a housing assembly with an elastic portion on the bottom plate that abuts and electrically connects with the electrode assembly, eliminating the need for welding and allowing for a single-sided coating of active material, while an arc-shaped elastic portion can disconnect during high-temperature events to prevent electrical connection, and a composite second housing with a positive temperature coefficient material for automatic blocking.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If welding is used to connect electrode plates to conductive assembly and housing, then electrical connection reliability is improved, but manufacturing complexity and cost increase due to weld burrs and weld marks piercing separator
Solution Approach 1:
The patent extracts and eliminates the welding process from the battery assembly. Instead of welding electrode plates to conductive assembly and housing, the invention uses direct contact through elastic portions that provide both mechanical support and electrical connection, completely removing the source of weld burrs and weld marks that could pierce the separator.
Solution Approach 2:
The patent replaces the welding mechanical system with an elastic contact system. The elastic portions of the conductive assembly and housing bottom plate make direct mechanical contact with the electrode plates, providing both structural support and electrical connection without the harmful effects of welding.
2Reliability
If double-sided coating of active material on electrode plates is used, then electrical connection and active material utilization are improved, but energy density decreases due to transfer bonding structure requirements
Solution Approach 1:
The patent extracts and eliminates the transfer bonding structure from the electrode plate design. By using elastic contact at the edges of the electrode plates, the invention removes the need for transfer bonding areas, enabling single-sided coating and thereby increasing the active material utilization and energy density.
3Strength
If rigid housing structure is used, then structural strength is improved, but safety decreases during high-temperature cycling, overcharging, or over-discharging due to inability to cut off electrical connection
Solution Approach 1:
The patent introduces dynamic characteristics to the housing structure through elastic portions. These elastic portions can deform under abnormal conditions (high-temperature cycling, overcharging, over-discharging) to cut off electrical connections, providing a safety mechanism while maintaining structural strength through the overall rigid housing design.
Solution Approach 2:
The patent changes the physical state of the housing structure by incorporating elastic portions that can change their contact pressure and electrical conductivity under different conditions. During normal operation, they maintain firm contact for reliable electrical connection; during abnormal conditions, they deform to cut off connections, thus adapting to different operational states.
4Reliability
If elastic portion height is increased to ensure firm contact and electrical connection, then connection reliability is improved, but energy density decreases due to increased housing space occupation
Solution Approach 1:
The patent optimizes the height parameter of the elastic portions to achieve a balance between connection reliability and energy density. By carefully controlling the elastic portion height, the invention ensures sufficient contact pressure for reliable electrical connection while minimizing the space occupied in the housing, thereby maximizing the energy density.
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
This design enhances the reliability of electrical connections, reduces internal short circuit hazards, simplifies the manufacturing process, increases energy density, and improves safety by preventing electrical connections during abnormal temperatures.
Implementation Method 1
The bottom plate contains an elastic portion that protrudes toward the first housing
Implementation Method 2
when the battery generates gas during high-temperature cycling, overcharging, over-discharging, or the like, the elastic portion can be elastically deformed and switch to the second position, so as to cut off the electrical connection
Implementation Method 3
a composite second housing with a positive temperature coefficient material for automatic blocking
Data Source
AI summary
A battery including a housing assembly, an electrode assembly, and a conductive assembly. The housing assembly includes a first housing fixed on a second housing. The second housing is provided with a cavity and includes a bottom plate. The electrode assembly is disposed in the cavity. The bottom plate contains an elastic portion protruding toward the first housing. The electrode assembly includes a first electrode plate and a second electrode plate stacked together. A surface of the first electrode plate facing back from a center of the electrode assembly contains a first blank foil region uncoated with a first active material and electrically connected to the conductive assembly. A surface of the second electrode plate facing back from the center of the electrode assembly contains a second blank foil region uncoated with a second active material. The elastic portion is electrically connected to the second blank foil region.