Dead battery?

[hiker]

Just wanted to check if I should take this to recycling or is there a fix for this?

One of my two AGM batteries doesn't seem to take a charge, never reaches full charge, the Volt meter shows it at 4.0 to 4.4 wildly moving between numbers.
Bought in 2019 but not use much.


I bought twin batteries:
https://www.amazon.com/gp/product/B007Q ... UTF8&psc=1

in 2019

I haven't used them much at all, as they are heavy and even on longer car trips I was able to recharge smaller batteries while driving. Still these might be useful if I was car camping and not moving very far etc so I could not do much charging.
The other one still shows a 12.? charge and the trickle charger shows it reaching full charge.

[SleepGeek]

Those are good batteries - when new and at >12V.

So the one that doesn't charge to 12V is no good any longer.