Fluid Spring Battery Stack Pressure Control With Vacuum Compression
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing battery systems face challenges in actively controlling the pressure exerted on battery cells, which can lead to non-uniform pressure distribution and increased risk of thermal runaway propagation. Additionally, current solutions require high energy consumption for maintaining fluid pressure and are not efficient in managing pressure changes over the battery's lifetime.
Innovation Solution
The integration of fluid springs with an elastic device into the battery stack allows for controlled pressure adjustment using an adjustable underpressure mechanism. A control unit monitors safety critical situations, such as crashes or thermal runaways, and adjusts the fluid pressure in the fluid springs to mitigate these risks, while also reducing energy consumption and improving pressure uniformity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stress or pressure
If high fluid pressure is used to maintain battery cell pressure, then the pressure control function is achieved, but energy consumption increases
Solution Approach 1:
Instead of using positive pressure to maintain battery cell compression, the patent applies negative pressure (vacuum) to the fluid springs. This inversion allows the atmospheric pressure to do the work of compressing the battery cells, while the vacuum system only needs to maintain a partial vacuum rather than counteract full atmospheric pressure, significantly reducing energy consumption.
Solution Approach 2:
The patent introduces fluid springs as an intermediary mechanism between the vacuum system and the battery cells. These fluid springs convert the vacuum pressure into mechanical compression force, providing uniform pressure distribution across the battery cells while allowing independent control of the vacuum level to manage energy consumption.
2Stress or pressure
If rigid pressure plates are used to compress battery cells, then pressure application is achieved, but pressure distribution uniformity deteriorates
Solution Approach 1:
The patent replaces rigid pressure plates with flexible fluid springs that can conform to the shape of the battery cells. These flexible fluid springs distribute pressure uniformly across the cell surfaces, preventing localized stress concentrations while maintaining the required compression force for thermal management and electrical contact.
3Stress or pressure
If fixed pressure is applied to battery cells, then initial pressure requirements are met, but adaptability to battery expansion and contraction deteriorates
Solution Approach 1:
The patent implements a dynamic pressure control system where the vacuum level in the fluid springs can be adjusted in real-time based on battery state. The control unit monitors battery parameters and modifies the vacuum pressure accordingly, allowing the system to adapt to battery expansion during charging, contraction during discharge, and long-term aging effects, maintaining optimal pressure throughout the battery lifecycle.
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 solution enables active control over pressure in battery systems, reducing the risk of thermal runaway propagation and improving the overall performance and safety of the battery stack. It also minimizes energy consumption and maintains uniform pressure distribution throughout the battery's lifetime.
Implementation Method 1
one or more fluid springs configured for holding a fluid; one or more fluid pressure adjusting means for adjusting a fluid pressure within at least one fluid spring
Implementation Method 2
one or more fluid pressure adjusting means for adjusting a fluid pressure within at least one fluid spring; The pressure exerted by the fluid springs on the adjacent battery cells is controlled by an adjustable underpressure of the fluid in the fluid springs
Data Source
Figure 1A
Figure 1B
Figure 2
AI summary
The present invention refers to a battery system (100) comprising a stack comprising a plurality of battery cells (101, ..., 1012); fluid springs (30); and fluid pressure adjusting means (12,). The fluid springs (30) are positioned between a first and a second end plate (40a, 40b), and are configured for exerting a pressure on the battery cells. At least one of the fluid springs (30) comprises an elastic device, the elastic device having a predefined Young's modulus. The fluid pressure adjusting means (12) is connected to one or more fluid springs (30) comprising an elastic device is configured to generate an underpressure in the fluid within the connected fluid springs (30). Also, the battery system allows for avoiding or minimizing the risk of spill-over of a thermal runaway between different cells of the battery system. The present invention also refers to method for operating the battery system.