The relationship between internal resistance and capacity of a battery has two meanings

The relationship between battery internal resistance and rated capacity, as well as the relationship between internal resistance of the same model of battery and state of charge (SOC). More than a decade ago, people attempted to use changes in the internal resistance (or conductivity) of valve controlled sealed lead-acid batteries to online detect battery capacity and predict battery life, but it was not successful; People have increasingly high requirements for the high current discharge capacity of power batteries, which requires minimizing the internal resistance of the battery as much as possible.

Therefore, this article will further explore and clarify the inherent relationship between the internal resistance and capacity of some commonly used batteries. Valve controlled sealed lead-acid batteries have gradually replaced open flow electrolyte lead-acid batteries and are widely used in postal and telecommunications power supplies, UPS, energy storage power systems, etc. Power type valve regulated sealed lead-acid batteries have been widely used in electric power assisted vehicles. These fields all require online detection of the state of charge of batteries.

The relationship between the internal resistance of a battery and its state of charge (SOC) refers to the ratio of the capacity that a battery can release to its rated capacity. This data is crucial for the postal and telecommunications power supply system and the power battery pack currently in use.