Meaning
Measured limits define the point at which a loss or gain of weight in a cell indicates a significant chemical or physical transformation. This mass change threshold is used primarily during safety testing to identify electrolyte leakage or degasification. It provides a non invasive way to monitor the integrity of a sealed housing.
Detection Parameter
Gravimetric sensors track the weight of a test sample during prolonged exposure to heat or cycling. If the weight fluctuates beyond the mass change threshold, the test is often terminated to prevent a thermal event. Small changes may indicate the slow evaporation of volatile compounds.
Safety Evidence
Regulatory filings often cite the stability of a cell relative to this limit as proof of manufacturing quality. Crossing the mass change threshold during a standard crush or nail penetration test marks a failure of the containment system. It identifies the moment when the internal pressure forces material out of the casing.
Analytical Value
Precise weighing allows for the calculation of the rate of degradation over thousands of cycles. Staying below the mass change threshold confirms that the active materials are not being lost to side reactions that produce gas. This metric helps in estimating the end of life for grid scale storage assets.
