State of Charge – or SoC – reflects how much usable energy a battery can deliver at a given moment. While it is shown as a percentage of the nameplate capacity, the actual energy you can dispatch from the battery depends on the usage conditions like operating load and temperature. When batteries are not actively being cycled (e.g. during storage, or when your system is inactive for several months), they gradually lose their energy (self-discharge). Prolonged periods without cycling could result in a deep discharge which impairs the battery’s performance and reduces its lifespan. Due to small differences in internal resistance from cell to cell, cell SoC variations within the same battery (imbalance) could evolve, which compromises performance.
Another challenge with batteries’ SoC is that the SoC calculated by the battery’s BMS has some inherent inaccuracies that could cause the displayed SoC to deviate from the real SoC. A regular SOC maintenance cycle should be performed to recalibrate the BMS’s calculated SoC to ensure the displayed SoC reflects the real SoC.
Foregoing regular SoC maintenance could lead to higher replacement costs and unexpected downtime. As performance becomes less predictable, planning grows more complex and operational risk increases. Without disciplined oversight, SoC imbalance can quietly undermine reliability and shorten service life.
To avoid performance loss and reduced lifespan of your batteries, timely SoC maintenance should be performed. Most battery manufacturers publish recommended SoC maintenance procedures that typically include a charge / discharge cycle and cell balancing at a certain time interval. Renewance has the proper equipment and experience to perform SOC maintenance on your batteries, warranting uncompromised performance and longevity.
