New battery charger technology?

[Huw Powell]

(resending from my subscribed address)

The old style were just power supplies, basically - 15 volts or whatever 
as long as they were on, which was really hard on batteries if they got 
left on too long.

The new ones are quite complex, and monitor the actual battery voltage. 
  They turn off when the battery is at some voltage like 13.2, then back 
on when/if it drops to 11-something, and stop charging when finished, 
lighting up a green light or what have you.  I think that's what the 
manual for mine said it did, anyway.

They are so light I don't even think they have transformers.

Basically I think they "charge with current" rather than "voltage".  I 
have an old but similar B&D "univolt" charger (for cordless drill 
batteries etc.) that will charge any voltage battery that can be plugged 
into it.  Tells you when it's done, and never heats the battery up.

Probably about half of this is true, I'll leave it up to you to guess 
which half, since I don't know.

On 8/2/2011 8:35 PM, Mike Arman wrote:
 >> From: Huw Powell <audi at humanspeakers.com>
 >
 >> Subject: Re: Charging C4 Battery using jumper positions
 >
 >>
 >> I'd also recommend buying a new charger, the modern ones are much more
 >> battery-friendly, and the $40ish 2/10/50A ones can start a car.
 >
 >
 >
 > I'd be interested in hearing a bit more about this new battery charger
 > technology. I have this ancient device which appears to have been signed
 > on the back by some guy named "Thomas Alva Edison" (whoever he was) in
 > my hangar that I've been using for years - always interested new and
 > improved ways to spend money on tools and equipment!
 >
 >
 > Best Regards,
 >
 > Mike Arman
 > 90V8Q, other stuff with lead-acid batteries, too.