Icom battery packs power Icom transceiver radios. The size and voltage of the battery pack vary, depending on the Icom unit it powers. The ability to repair an Icom battery pack depends on the type of battery cells it contains. Many Icom battery packs contain nickel cadmium (NiCad) cells, so you can usually repair them, but later models contain lithium cells, so the process won't work. The only option then is to send the battery for repair or purchase a replacement.
Open the battery cover on the Icom transceiver. Look at the label on the Icom battery pack to make certain it contains NiCad cells; it is clearly marked. If it does contain NiCad cells, proceed with the following steps, If it does not, these steps will not be helpful.
Charge the Icom battery pack in the usual manner. It's likely to hold a small charge, even if it needs repairing. Repairing a NiCad battery involves a complete discharge, as this procedure revitalises the cell structure.
Disconnect the charger once the battery is fully charged. Turn on your Icom transceiver and tune it to a receiving channel. Turn up the volume as much as possible so you use more energy from the battery that needs repairing. You may want to cover the transceiver with a cloth if the noise becomes too loud.
Leave the battery to discharge until the transceiver doesn't work. Turn off the transceiver and leave it to rest for at least 30 minutes.
Turn on the Icom transceiver after about 30 minutes. You should be able to tune it to a channel and hear it. Leave it to operate until it stops again, then turn off the transceiver.
Repeat the process as many times as necessary until finally nothing happens when you turn on the transceiver. The number of times you need to do this depends on the battery's condition, but it's not likely to be too many times. Every time you repeat the process, crystals in the battery cells break up into smaller crystals and start to get back to the size they were when you first purchased the battery. Tiny crystals retain more energy than larger crystals, so this process gradually repairs the battery.
Put the Icom battery pack back on to charge once the transceiver no longer turns on. Leave it to charge, but expect a fairly long wait. The battery pack will be completely discharged and will need a reasonable amount of time to fully recharge.
Turn off the charger once the battery is full. Turn on your Icom transceiver. You will find the battery is repaired and the transceiver will operate the way it did when you first bought it.
If your battery is in really poor condition, you may need to repeat the procedure from the start before it operates correctly. If, after a couple of attempts, there's no improvement, then your only option is to replace it. You can also use the above process if your battery contains nickel metal hydride (NiMH) cells.