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Jim Yanik Jim Yanik is offline
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Default Automotive battery charging

Cydrome Leader wrote in
:

Jim Yanik wrote:
Cydrome Leader wrote in
:

mike wrote:
On 3/27/2012 4:59 AM, klem kedidelhopper wrote:
I'm having a discussion on another group with someone about
battery charging. I often charge my batteries including automotive
off my bench power supply. He was telling me that smooth regulated
DC is not the best thing to use for charging batteries. He said
that half wave rectified unfiltered DC will prevent the growth of
"dentrites" that can eventually extend and short out the plates.
This is the first I've ever heard of this. Does anyone have any
further insight on this? Lenny

The dendrite thing is what shorts sealed NiCd batteries.
"burp charging" is said to reduce that problem.

there are a variety of "desulfator" gadgets for lead acid batteries.

Here's what I've learned about lead acid batteries.

- small ones suck and die in a few years, no matter how you baby
them - big ones last longer and are expensive to replace.
- more and more batteries are from china and just pure crap.

that's really it. They all go bad in the end, usually when you need
them.

I blew up my set of UPS-270 batteries by charging them on a charger
that failed with the series regulator going dead short.

They just replaced several tons of UPS batteries at work. Some of
the batteries were only months old, but they're still all going back
to the smelter as part of the trade in agreement. I tried to buy
back the new ones from the guys loading up the pallets, but they
didn't want to get fired, and somebody does count them up.



Of course,they count them.

the trick is to have substitutes to -swap- for the good ones you
want. B-) the loaders don't care as long as the numbers all add up.


last pile of duds I had went into the alley. Scrappers snatched them
up pretty fast.


yeah,metals prices have climbed quite a bit;last time I needed a new car
battery,the prices were at least 50% higher.

but if you think you'll get another opportunity to score on a all-out
swap,then save a few duds in anticipation of that day.

--
Jim Yanik
jyanik
at
localnet
dot com