I have a PRC-127EFJ, essentially an EF Johnson 5100-series VHF handheld radio with a 3600ah NiMH battery.  It's at least 10 years old and may have been sitting uncharged for a few years.  When I turn on the radio after a full charge, it starts chirping with a low battery warning after 15 minutes.  However, it'll stay on continuously for 8 hours when receiving the local NOAA Weather station.  With a low battery warning, the HT switches to 1 watt, which isn't enough power to hit the local weather spotter repeater in the rain.

Do you think this battery is really toast?  Is there any way to save it?

10+ year old NiMH?  Yea, she's toast.  It can pull enough voltage to receive, but not enough to TX.

It's toast.

Probably has a cell that's failed short, so the voltage quickly drops enough to trigger the low battery warning.

At least it looks like replacement batteries are still out there for them.

Yes, I'm finding Chinese knockoffs, but no OEM batteries.

I have a 5100.  I takes the xts 5000 batteries.
There are lots of those out there. Attached File

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