Frequent deep discharge of energy storage batteries

How does deep discharge affect battery life?

Depth of Discharge (DOD) A battery’s lifetime is highly dependent on the DOD. The DOD indicates the percentage of the battery that has been discharged relative to the battery’s overall capacity. Deep discharge reduces the battery’s cycle life, as shown in Fig. 1. Also, overcharging can cause unstable conditions.

What is a deep discharge battery?

Deep Discharge Battery: This refers to a battery that has been discharged beyond its recommended limit, which causes harm to its performance and lifespan. Deep discharging a regular battery (e.g., lithium-ion, NiMH) puts excessive stress on it, and over time, it won’t hold charge as well.

What happens if a battery is fully discharged?

For example, if half of your battery is discharged, its DoD will be 50%. In other words, the depth of discharge shows the amount of energy left in a specific battery and lets you know how long you can use it before putting it on the charge. Generally, it is not a good practice to discharge the battery fully, as it may damage the whole system.

Does a higher depth of discharge make a battery better?

The better performance of a battery is not necessarily connected to a higher depth of discharge. For most batteries, it is advised to avoid high depth of discharge. When we say a battery has a higher DoD, it means we can use more energy before recharging it.

Why do batteries need a deep discharge cycle?

While deep cycles are necessary for certain applications (like in electric vehicles or solar power storage), they take a greater toll on the battery. A deep discharge cycle can cause chemical degradation and structural changes within the battery, which accelerates its aging process.

Can a deep discharged battery cause overcharging?

Increased Heat Generation: Deep discharge can increase the likelihood of overcharging once the battery is plugged back in to recharge. If the charger continuously tries to force power back into a deeply discharged battery, it may overheat, causing safety risks like battery swelling or leakage.