Home > Knowledge > Content
Valve controlled sealed lead acid battery
- Jul 26, 2018 -

At present, valve-regulated sealed lead-acid batteries have gradually replaced open-ended flow electrolyte lead-acid batteries, which are widely used in postal and telecommunications power supplies, UPS, and energy storage power systems. Powered valve-regulated sealed lead-acid batteries have not only been widely used in electric bicycles. These areas require online detection of the state of charge of the battery.

The relationship between the internal resistance of the battery and the state of charge

The state of charge SOC of a battery refers to the ratio of the capacity that the battery can discharge to its rated capacity. This data is important for postal and telecommunications power systems and power battery packs in use.

In 1992, David O Feder published tests and statistics on valve-regulated sealed lead-acid batteries (VRLA) using the MIDTrONic Celltron and Midtron conductivity tester. Figure 1 shows the distribution of discharge time and battery conductance (reciprocal of internal resistance) for 336 1000Ah sealed lead-acid batteries with 263 A discharge to 1.80 V. It can be seen that there is a linear correlation between them, and the correlation coefficient R2=0.825.

It has thus been proposed that for valve-regulated sealed lead-acid batteries used in-line, the measured conductance values can be used to estimate their remaining capacity. Although I have repeatedly denied this view from the objective reality more than a decade ago, I have been recognized by many peer experts. But today there are still some people who have not tried to cite the above-mentioned outdated ideas without thinking, and therefore revisit the "stick" of the above viewpoints.