[Elecraft] [OT] Lead-acid battery question

[Vic K2VCO]

I know there are those on this list who can help me.

I have a 5 kW generator at my house. It runs automatically once a week for a half hour to 
charge the (sealed) battery. The first battery lasted for about 10 years! The present 
battery is about 2 years old.

Some months ago, I noticed that it wasn't running. I found the battery dead. I took the 
battery back to Batteries Plus where I got it; they charged it overnight and tested it 
under load. They said the battery was OK. When I started the generator and checked the 
charging voltage, it was 13.8V which I thought was marginal, so I replaced it.

Yesterday the generator would not start. The battery voltage with no load was 11.5V. I 
left it on the charger all day. Then this morning I checked the voltage and it was 13.5V. 
The generator started up and the charging voltage was 14.5V.

Do I have a bad battery?

-- 
Vic, K2VCO
Fresno CA
http://www.qsl.net/k2vco/