Why include SWIR Sensors in Electric Vehicle Battery Production Monitoring and Quality Control Testing?
Quality control testing of batteries is vital to ensure that they meet stringent safety, performance, quality, and quality standards. Currently, leak detection methods are slow and inaccurate, and even tiny leaks can shorten the battery’s life, impact performance, and increase warranty costs. Even worse, leaking can shortcircuit electrical systems, set fires, or cause damage to battery components.
A battery can be non-destructive tested before it leaves the factory. Automated Xray inspection can reveal defects in cells before they leave the factory. This prevents defective cells becoming part of battery modules. The cell structure is also important for quality control. Rolled cells are easy to inspect in 2D. But stacked cells require 3D computer imaging. This makes it difficult to interpret a transmissive-X-ray image.
Engineers assess a battery’s condition during manufacturing by measuring the state of charge or discharge. The condition of the battery’s busbar is also evaluated. This long conductor is isolated from the ground and is responsible to distribute current throughout the pack. The busbar’s condition is important because it is the metric that determines the weld resistance for batteries. A weld with a low resistance can result in excessive heat and early failures. Engineers can identify defective modules quickly by measuring their resistance before they are operational.
To estimate the battery pack’s useful life, it is important to perform performance testing. It is possible to reduce the usable life of a lithium-ion battery pack by charging it too often or discharging it too frequently. The battery management system, or BMS, uses this information in order to maintain cells within safe operating limits. BMS must also include a precise charge estimator to calculate SoC.
SoC is more difficult than temperature and voltage. It must be calculated using proprietary parameters.
SWIR can be used to adapt the Lithium-Ion Battery Testing Process
High resolution, wide field of view, extended SWIR cameras and high resolution can all be used to solve important inspection issues in lithium-ion batteries. This will allow them to meet increasing quality and performance requirements.
When using SWIR Vision’s Acuros sensor it provides imaging through the LiIon separator using SWIR wavelengths. These cameras or sensors provide the alignment accuracy required for inter-layer electrodes, resulting in greater energy storage capacity as well as longer battery life.
These sensors are adaptable as quality control features throughout production due to their ability to see through things and send back high-resolution imagery at a rapid rate. We expect rapid adoption of SWIR cameras for battery testing.