My solar power system contains a lead-acid battery but as soon as I use the inverter to power some load, the voltage drops instantly by 1 volt.
Why does this happen? And is it proportional to the load (bigger load = bigger voltage drop)?
batterieselectricity
My solar power system contains a lead-acid battery but as soon as I use the inverter to power some load, the voltage drops instantly by 1 volt.
Why does this happen? And is it proportional to the load (bigger load = bigger voltage drop)?
Best Answer
Take a look at this graph from here: -
From All About Batteries, Part 3: Lead-Acid Batteries.
It's a typical 12 volt lead-acid battery discharge characteristic and it shows the initial drop from about 13 volts to around 12 volts occuring in the first minute of a load being applied. Thereafter, the discharge rate doesn't unduly affect the output voltage level until the battery gets quite depleted of stored energy.
This site explains in detail why that initial drop of terminal voltage is steep compared to the much slower drop in voltage that occurs afterwards: -