Discharging a lead acid battery below its recommended voltage can cause permanent damage to the battery. It can also reduce the battery’s capacity and lifespan. Therefore, it is essential to avoid discharging the battery below its recommended voltage level. This will ensure its long-term health and performance.
Being familiar with a lead acid battery voltage chart can help you to understand the state of your battery at a glance. What voltage should a fully charged lead acid battery be? A fully charged lead-acid battery should measure at about 12.6 volts.
Temperature affects lead acid battery voltage levels. The voltage level of a lead acid battery increases as the temperature decreases and vice versa. Therefore, you need to consider the temperature when measuring the voltage level of a lead acid battery. At what voltage level is a lead acid battery considered fully charged?
Personally, I always make sure that anything connected to a lead acid battery is properly fused. The common rule of thumb is that a lead acid battery should not be discharged below 50% of capacity, or ideally not beyond 70% of capacity. This is because lead acid batteries age / wear out faster if you deep discharge them.
This means that if you (accidentally) short-circuit a lead acid battery, the battery can explode or it can cause a fire. Whatever object caused the short-circuit, will probably be destroyed. Because lead acid batteries can supply such high currents, it's important to assure that you use the right wire thickness / diameter.
A lead acid battery should never be below 11.80 volt at rest. ↩ 'bad' battery protection solutions will just start to oscillate as the battery voltage recovers (above the cut-off threshold) when the load is removed. I bought a cheap 20 Euro unit and it was effectively useless because of this problem. ↩