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How to determine if a battery is fully charged:
The WISPR battery will charge to 26.11 volts. Even once the battery voltage reaches 26.11 on the charger screen, that does not mean it is fully charged. You should wait until the charger sounds to indicate the battery is finished and the screen reads “END: FINISH” to get the most out of the battery. You will also recieve multiple beeps once a battery is completly charged.
Battery Charging Modes:
Fast Charge - This mode directs the charger to only complete the first charging phase, constant current (CC) charging. The charger applies a high enough voltage to cause current to flow into the battery, up to the max current you've set. This will mostly charge the battery, but there will still be some unused capacity with this mode.
Balanced Charge - For maximum health, you should always balance charge your batteries. This is also why your battery has a second plug. This second plug is called the “balance plug” and is used by your charger to individually monitor and balance charge each cell.
Storage Charge - This option should be used if you are not planning on using your battery for an extended period of time (24 Hours or longer). You should never store a fully-charged LiHV battery. Instead, it should be set to the storage charge setting and the voltage decreased to “storage voltage”, which is 3.8 to 3.85 volts per cell.
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Check that the balancer plug (white plastic plug on the battery) and the XT90 plug are properly plugged ininto the respective ports and wires coming from the charger. Wires on both ports (balancer and XT90) should be plugged in tightly.
Verify that you have the correct charging mode set on the charger.
If these options are not the issue, use the charger to make sure all cells are balanced. You can check the cells by pressing the stop button once, the start button once, and then the up arrow once. If you see a damaged cell, (one reading completely different from the others) replace the battery immediately.
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