The 29.2V 20Ah LiFePO4 battery charger is designed to charge 24V LiFePO4 batteries. The low resistance in the Lithium cells allow the battery to accept the full output from the charger. With a constant 20A current, it takes around 100Ah/20A=5hrs to fully charge a 24V 100Ah LiFePO4 lithium battery.

If the correct voltage limit is set for the LiFePO4 lithium ion battery you are charging, there should be no issue leaving a lithium ion battery on the charger overnight. LiTime Battery uses a LiFePO4 cell giving a nominal voltage of 12.8v and a fully charged voltage of 14.6v. A charger with 14.4-14.6v CC/CV output will do the job with consideration not to exceed roughly 1C maximum current output of the charger. As long as the CC/CV profile is used, the maximum voltage is at the correct level and the current is not excessive, you will achieve a safe and full charge on your battery.

To determine your charging speed, take the amp hour rating of your battery and divide it by the output current of your charger. For example, a 100 amp hour battery (Ah) would charge in 100AH/10A=10 hours with a 14.6V 10A LiFePO4 lithium battery charger.

For most applications, a charging time of 3-10 hours provides the longest lifespan for your LiFePO4 lithium battery. But if you have an application where you need rapid charging, you can choose a charger with a higher output current. For example, you could use a 40 amp charger with a 100Ah battery for a 2.5-hour charge time.

It depends on the voltages of your LiFePO4 lithium batteries. LiTime 14.6 volts charger is recommended for 12V LiFePO4 lithium batteries. And LiTime 29.2 volts charger is recommended for 24V LiFePO4 lithium batteries.

It is always important to match your charger to deliver the correct current and voltage for the LiFePO4 lithium battery you are charging. For example, you wouldn't use a 24V charger to charge a 12V LiFePO4 lithium battery. It's also recommended that you use a charger matched to your battery chemistry. Additionally, when charging a LiFePO4 lithium battery with a normal lead-acid charger, you would want to ensure that the charger does not have a desulfation mode or a dead battery mode.