[ausev] New EV Use

[Chris Robison]

Sarah & Erik wrote:

  > Charging promotes the shedding of the active plate material which
> falls and gathers at the bottom of the cell, which contributes to
> shorter battery life. Definitely equalize and make sure your batteries
> are fully charged before you worry about overcharging a flooded
> battery, but there is a reason to care beyond energy and water waste,
> AFAIK.

Something tells me I've read about this before, but I've forgotten about 
it. Time for some more research  :o)


>> Here's the situation as I understand it. Lead acid batteries like to be
>> full or as close to it as possible. Aging of a lead-acid battery is an
>> unstoppable process, but the more full the battery is at any given
>> moment, the slower it is aging.
>>
> /snip
> 
> Yes, but there's a worry that I didn't understand until I had
> batteries to take care of, and it's that people always talk about
> charging and not running them down and they'll last longer the longer
> they charge. Yes to all of the above, but the electrochemist from US
> Battery said it's not a big deal if they sit for an hour or several
> discharged. Days is bad, but you don't need to run for the plug when
> you get home. Charging sooner is always better, but he said basically,
> there are bigger things to worry about besides charging the first
> instant you can. That being said, charge as soon as you can =)

Absolutely. It's all a matter of proportion, which I don't do very well 
at describing. It's true that a battery ages many times more quickly 
when its discharged than when it's charged, due to sulphation. However, 
even that is *still* pretty slow. So it's not critical to charge it 
right away -- it's not the couple of days of sitting discharged that 
kills a battery. It's the couple of days, chronically, hundreds of times 
over the life of the battery, that reduces longevity. And then of course 
there's that several weeks at once...  :o)

   --chris