I have an 8D wet cell battery
(~220Ah) from 2004 as a house battery
. The boat is most often in its marina berth, with a 5-step shore-powered charger
on the battery. I am a liveaboard
, using the battery constantly.
After I last topped up the battery, the charger
(which was usually in float mode) keeps being in absorption mode, and the battery immediately gases and loses a lot of water
. The specific gravity never indicates more than 50%-75% full, and if I stop the charger, the battery goes down to 10.5V after a day.
It seems obvious to me that the battery is dead (and not prematurely), but I'm puzzled about its behaviour. I thought that a dead battery simply had close to none capacity? I.e., I would expect it to charge very quickly and discharge in the same manner. In my case, it looks as if the battery cannot be charged at all.
Does this indicate something specific about the way the battery died? Is there maybe something wrong in the way I handled it?
I am now on the search for a new battery, and I'm hesitating. AGMs and gel seem to have more capacity for the same size (up to 260Ah for an 8D apparently), and 200Ah is a bare minimum for my usage. On the other hand, I would have to change my regulator
, and it sounds like these types don't like being kept close to gassing charging
regimens. Plus, it's difficult knowing which brands are the good ones here in New Zealand
, as the choice is different from what's available in the US and Europe
. I can see Ritar, Odyssey, Vision, Amp-Tech, Prolite... Trojans and Optima are available but not in the capacity I need, apparently.