Battery Efficiency

Battery efficiency, also known as round-trip efficiency, is the charging and discharging efficiency of the battery or the loss degree of the battery in use. According to the laws of physics, the transfer of energy from one form to another results in energy loss. In this case, the battery is converted from electrical energy to chemical energy in the process of charging, and from chemical energy to electrical energy in the process of discharging. In general, the loss of lead-acid batteries is much higher, 15-20%, while the loss of most lithium-ion batteries is much lower, 2-8%.

Another problem with lead-acid or lead-carbon systems is that they take much longer to charge than lithium systems. The lead-acid charging cycle (large capacity absorption phase) may take 2 to 4 hours, depending on the depth of discharge. This means that during severe or intermittent extreme weather, the charging efficiency may be very low and may not be fully charged, which will shorten the battery life. On the contrary, lithium batteries can charge quickly (1-2 hours) and absorb energy efficiently.

Deep cycle lead acid efficiency = 78% - 85%

Lithium LFP battery efficiency = 92% - 98%

Also different from lead-acid batteries, lithium-ion batteries can endure partial charge state (POS) for a long time without plate degradation or sulfate problems. Regular charging of lead-acid batteries (which may occur in winter) will greatly shorten the life of most lead acid (AGM or GEL) batteries.

In addition, the voltage drop of lithium is very slow under load. Even under high load (48V), the fluctuation of lithium usually does not exceed the nominal value of 1-2V. The reason is that compared with lead-acid battery, its internal resistance is much lower. Low resistance leads to the biggest advantage of lithium, that is, low loss in the process of charging and discharging, thus achieving a high round-trip efficiency.

So if you are looking for the best battery type in energy storage application, we suggest you try our solar LFP battery. High efficiency lithium-ion battery makes your home energy storage solution more convenient and simple, and the cost of money is more worthwhile.