Battery Housing Internal Insulation for Electrical Safety
Solution Overview
Problem
Electrochemical energy stores, such as lithium-ion batteries, face challenges in preventing undesired currents between cells due to shared electrochemical potential of conductive housings, leading to operational hazards and inefficiencies, especially when assembled into modules.
Innovation Solution
The housing is partially or fully covered with an electrically insulating material to prevent electrical potential disruptions, using a liquid electrolyte and an opening covered by overlapping insulating material for safe and sealed internal insulation, allowing for cost-effective and stable battery operation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If the housing is made of conductive material, then mechanical strength and structural stability are improved, but undesired currents between cells occur due to shared electrochemical potential
Solution Approach 1:
An electrically insulating material is introduced as an intermediary layer between the conductive housing and the cell units. This insulating layer prevents direct electrical contact while maintaining mechanical support, thereby eliminating undesired currents between cells while preserving the structural benefits of the conductive housing.
2Reliability
If the housing is fully insulated, then electrical safety is improved, but manufacturing complexity and cost increase
Solution Approach 1:
Instead of applying insulation uniformly across the entire housing, the insulating material is selectively applied only in regions where electrical isolation is required - specifically where cells are arranged and where electrolyte filling occurs. This localized approach maintains electrical safety while reducing material costs and manufacturing complexity.
Solution Approach 2:
The patent applies insulation partially rather than completely - specifically covering the interior surface where cells are arranged and the electrolyte filling opening, but not necessarily the entire external surface. This partial insulation achieves the necessary electrical safety while minimizing manufacturing overhead.
3Reliability
If external insulation is used, then electrical insulation is provided, but the insulation is subject to mechanical stress and requires stringent requirements
Solution Approach 1:
Instead of placing insulation on the external surface of the housing, the insulating material is inverted to be positioned on the internal surface, directly contacting the cells and electrolyte. This internal positioning protects the insulation from external mechanical stresses while maintaining its electrical isolation function.
Data Source
AI summary
An electrochemical energy store (10), comprising a housing (12) for accommodating at least one cell unit (24), wherein the housing (12) forms a receptacle space for the arrangement of the cell unit (24), wherein a surface (17) of the housing (12) facing the receptacle space is completely covered by an electrically insulating material (27), wherein the housing (12) also comprises an opening (20) for filling a fluid electrolyte into the receptacle space, and wherein the opening (20) is covered by two overlapping end regions (26, 28) of the electrically insulating material (27). An energy store (10) according to the invention permits a simple means of bringing about sealed internal insulation of a housing (12) accompanied by simultaneously improved manufacturability.