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Battery recommendation Answered


I'm looking for a rechargeable battery for a project and I'm not having any luck finding a suitable one.  Here's what I need:

The battery will need to be between 12 - 18v with between 1-2 amp.  This will be powering a set of speakers, so not really sure what type of amp hours I need.  The battery will need to fit into a tin lunch box.  

An idea I had was to use a 12 or 18v battery for Power Tools - not sure if it will work though.  I also found this, http://www.altex.com/12V-Lithium-Ion-Rechargeable-Battery-Set-LBP-124500-P150057.aspx not sure if it is powerful enough though.

Any thoughts/ideas is appreciated.  


Hobbyking has some nice lipos.

Try looking for some old lithium-ion laptop batteries, the set I have here is 4400mAh @ 12V, which would give 2 hours at 2A.

2x6 cell Ni-MH packs would give 14.4V and at least 1200mAh, but tend to be quite expensive, especially for higher capacites, as well as being reasonably heavy. The same is true for most drill batteries, although some cheaper ones use Ni-Cad cells.

Alternatively, a small sealed 12V battery out of a moped/small bike would have a good capacity, and can suppply a large current.

BTW, the address in the comment only gives this:
"The page you have requested cannot be found or has been removed."

Thanks for the advice. Is there some module I would need to force the throughput to 2A? Most notebook batteries I have seen have a much higher amperage.

Also, I tried the link again and it worked for me. But I have pasted it separately below to avoid clutter.


The current drawn depends on the load, so if the batteries are rated for a maximum current of 4A, and the speakers are rated for 1A, they will only draw 1A.

The link works now, and the battery pack there should work.

Hope this helps.

Do you know what type of battery life I would be looking at with that battery?

It will be hooked up to this Amplifier. http://www.electronickits.com/kit/complete/ampl/CANUK193.htm

With two 10 watt (RMS) 4 ohm speakers.

Thanks for the help so far Skinnerz

Just been looking at the spec for that amplifier, and you will only be getting 12W RMS with those speakers, which probably isn't a problem, but I thought I should point it out.

Good luck with the project.

So, theoretically I could be over powering the speakers at max Volume?

If so, I agree this shouldn't be much of an issue. For the space/purpose this will be used in, I shouldn't be using max volume.

Thanks for the help, i'm excited to get started!

You won't be over-powering anything, as 2x4Ohm will be 8Ohm, so it will just let less current flow, so less power, and the Amp doesn't mind having an 8 Ohm load.

(just remember to connect them in series, as putting them in parallel will make the load 2 Ohms, which the Amp will not like).

The batter is 4.5Ah, and the maximum current drawn by the amplifier is 2A, so you should be good for at least 2 1/4 hours at full volume, but it will probably go for significantly longer.


Found this as well today. Seems that it may fit the bill, not sure on capacity though.