The Horrors of Battery Maintenance

[FW]

....after the light comes on to indicate full charge I disconnect and after a few minutes I plug it in again. ...

Where are you disconecting it? If you leave the charger connected to the wall, and disconnect from the battery for a few minutes, it should work.

If you unplug the charger from the wall, it may not help. Lead acid battery chargers need to be plugged into the wall first.

You might consider investing in an Interacter charger.

[Sludge]

You might consider investing in an Interacter charger.

Absolutely.

I was going to get a burn tester and watt's up meter, but a friend in town said I can borrow his - do I really need to OWN one if I can borrow one every few months? I just need to make a point of going and actually getting it.

[FW]

...do I really need to OWN one if I can borrow one every few months? I....

Nope. Actually, for lead acid batteries, once a year is probably often enough. They don't need to be "exercised" like NiMH.

[crawford]

If you unplug the charger from the wall, it may not help. Lead acid battery chargers need to be plugged into the wall first.

I could swear I read in my manual for my old MLS/MR11 (which I keep as a backup and for my son to OW dive with) that you should never plug into the wall first. I get so confused with all this battery stuff. If you're right Forrest I've been doing it wrong for years.

[Jason B.]

If these chargers have an off/on switch, I can't see where it makes a difference what you plug in first and I'll have a hard time believing otherwise.

[crawford]

If these chargers have an off/on switch, I can't see where it makes a difference what you plug in first and I'll have a hard time believing otherwise.

I've got a charger for a Nimh and a lead acid, neither have an on/off switch.

[FW]

I could swear I read in my manual for my old MLS/MR11 (which I keep as a backup and for my son to OW dive with) that you should never plug into the wall first. I get so confused with all this battery stuff. If you're right Forrest I've been doing it wrong for years.

Did it have lead acid batteries? NiMH is battery first, wall last. NiCads weren't quite so picky, and Li battery chargers seem to come in both types.

[FW]

If these chargers have an off/on switch, I can't see where it makes a difference what you plug in first and I'll have a hard time believing otherwise.

It depends on how the chargers are designed to work. *Most* lead acid chargers need to "boot" with no battery attached, then connect to the battery to "analyze" the charge requirements.

NiMH chargers have to have to have battery connected during "boot" to "analyze" the charge requirements.

I have "boot" and "analyze" in quotes because this is an over simlification of how "smart" chargers work.

[crawford]

Did it have lead acid batteries? NiMH is battery first, wall last. NiCads weren't quite so picky, and Li battery chargers seem to come in both types.

Yeah, it's lead acid. I"ll read it again. Luckily I'm doing the NiMH correctly, since the replacement cost on it is 200-300 USD vs. 30 USD for the lead acid.

Oh the irony, I'm posting all this new advanced technology in the Fill Station and can't understand how a battery charger works

[saturation]

SLA batteries should be charged asap after discharge, this prolongs the life substantially. If you leave it for days, say after the last dive for a weekend, it will not recover very well or at all. The sooner you charge it, the less sulfation becomes a problem. Also, the less you run the battery down, the longer it will provide near virgin amp hours.

http://www.batteryuniversity.com/parttwo-35.htm

See the bottom of the page for the summary.