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finding the right charger for 12 volt lithium ion batteries

finding the right charger for 12 volt lithium ion batteries

finding the right charger for 12 volt lithium ion batteries


Let me first admit that I am total novice working on a pet project, so please give advice with this in mind.

Here's what I'm working with:

I'm looking at ordering 5 of these batteries, so I can wire each up to an emergency beacon light and have them be portable.

Here is a link to the exact beacon light model which I have 5 of:

Is it a good idea to use this kind of battery to power this light (and motor which spins the reflector)? I'm hoping they will run for roughly an hour without needing a recharge. How long do you think I'll get?

These batteries on Alibaba are cheap, but they don't come with a charger and I'm not sure how to find an appropriate one. If you could provide me a link to a compatible charger, that would be perfect. I believe overcharging would be a problem with these batteries so a charger that has auto shut off, or an explanation of how long to charge would be helpful.

Any help greatly appreciated.

RE: finding the right charger for 12 volt lithium ion batteries

Why on earth would you use an incandescent lit unit in a battery application?!?!? Crazy.

Why not:

Or these spectacularly tough, dependable xenon units: I found one laying in the surf 15 years ago running and it still works with the same battery!

Yes your crazy dangerous battery will run the badly chosen light for over an hour.

To charge your battery you will need a LiPo aware charger. I'd expect your best bet would be an RC charger.

If you went with Lead Acid batteries (+17AH) for about $50 a piece you could use more available chargers.

Anyway, back at the charger for the LiPo. You need to find one that can set to 12V worth of LiPo batteries.

This type might work:

Keep in mind you usually want temperature feedback to prevent a hot fire. Which the example above doesn't seem to embrace. Usually LiPo batteries of the style you're showing are used in engineered systems that have custom chargers provided.

Keith Cress
kcress - http://www.flaminsystems.com

RE: finding the right charger for 12 volt lithium ion batteries

Hi, thanks for the info.

So, the reason for the project is I got 5 of these lights with the incandescent bulbs for cheap.
What I'd like to do with them is have them as stage lights for a band. Since they'll be moved a lot, and it can be hard to find 5 outlets in different locations, it would be best to not have to plug them into a wall.

given this info, what is the best and safest choice for powering them? and keep in mind cheapest?


RE: finding the right charger for 12 volt lithium ion batteries

Roughly speaking, the battery you proposed will power the light you propose for
( 10 A-h / 4.3 A ) = 2.3 hours. ... probably a litle less because it's a high discharge current for that size battery.

For cheap, you could go with used car batteries.
I'd be inclined to go with motorcycle batteries, which are smaller and lighter, or with AGM or gel cell batteries as used in a UPS, which won't leak acid when knocked over. Those are all lead-acid batteries, so as ItSmoked suggested, they won't need a super fancy charger. It goes without saying, so I'll say it, that the batteries and the charger should be 12 volt nominal.

Mike Halloran
Pembroke Pines, FL, USA

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