Question: The batteries on my hand-held VHF radios do not seem to be lasting as long as the manufacturer claims anymore. I remember that with my old radio it had NiCad batteries and they always suffered from what people call “memory effect”. I didn’t think lithium-ion batteries had that problem. What’s up here?


Lithium ion batteries last longest if stored without a full charge.

Answer: As time goes on we are learning a lot about lithium battery technology. You are quite correct, lithium-ion batteries do not suffer from the memory effect that NiCad batteries had. With NiCads, if you were constantly re-charging the batteries before they were discharged to their maximum level, the battery would eventually remember the level of discharge and only function properly to whatever that level happened to be.

Lithium batteries have a different problem that can be easily overcome with a little attention to detail. We know now that Lithium batteries do not like being stored fully charged as has been the case with most batteries over the years. A lithium battery will last longest if stored for extended periods at about 40% full charge at 75°F. Storing lithium batteries at full charge can cost you as much as 20% of the battery’s capacity per year. So with any of your lithium powered electronic devices, its best to run the batteries down to the point where the battery gauge found on most of this equipment is showing about ½ charge, and store it in a relatively cool location over the winter. In the spring, just charge it up to full charge and you’re in business.

Your lithium batteries will last much longer, and give you the life expectancy you want by following the regimen described here.