SLA vs. NiCd/NiMH charging.

Lunal_Tic

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Are SLA batteries more sensitive to input charge voltage than NiCd/NiMH batteries? What happens if you've got a requirement of 12VDC 1.5A and you only give it 12VDC and 1A? Should I run the SLA down to nil or keep it topped off?

I've got two 12V lights, one is SLA and one is NiMH. The SLA says it needs 12VDC 1.5A and the NiMH 15VDC 1.5A but I noticed that the NiMH powersupply puts out about 18VDC unloaded. Assuming sag under load, could I use the same powersupply for both battery chems?

Thanks,
-LT
 

Lunal_Tic

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I forgot, anyone got a recomendation for a SLA charger that won't break the bank or bust the light?

-LT

Just checked the SLA and it's at 12.94V. According to the article above that's full. Odd that it came with the battery pre-charged.
 

SilverFox

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Hello LT,

Since most banks have some resources... /ubbthreads/images/graemlins/evilgrin07.gif might I suggest a Triton... /ubbthreads/images/graemlins/evilgrin07.gif

Tom
 

MrAl

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Hi there,

I've built LA battery chargers where all the circuit had
to do was maintain a set float voltage (calculate from
the cell voltage which i dont remember what it was offhand)
with a current limit. This has got to be easier than even
a li-ion charger because the spec's arent as critical.

Depending on the current requirement, perhaps a LM317 with
a series resistor on the input, where the output is set
to the float voltage. I've built a li-ion charger exactly
like that and it's posted on here (CPF) somewhere too.


Take care,
Al
 

Lunal_Tic

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SilverFox,

While I appreciate your interest in my impending change of career, I can't see dropping $130 on a charger for my $35 light. Besides not all bank robbers have EE degrees and that's what that bugger looks like it requires to operate. /ubbthreads/images/graemlins/nana.gif

MrAl,

That actually sounds fun until I try to translate it to Japanese. Maybe I'll look into it when I'm back stateside. I may also try to track down the Japanese distributor for these things and see if they'll sell a charger for a reasonable price. I've got a number of DIY projects on the list but have not gone after them because of my limited knowledge in both electronics and Japanese.

Thanks for the ideas,
-LT
 

SilverFox

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Hello LT,

On a more practical note /ubbthreads/images/graemlins/smile.gif perhaps you could pick up a spot light that runs on a SLA battery. They have a charger included in the package.

Tom
 

Lunal_Tic

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Oh yeah right. Just what I need another light . . .

Hey wait a minute, I always need another light. That's why I'm here isn't it?

-LT
 
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