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Li1705 Battery Cells Replacement.

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Li1705 Battery Cells Replacement.

Postby Jono-08 » Tue May 27, 2008 10:08 am

Hi All

I'm replacing the cells in my Amilo Li1705 battery because it holds its charge for about just under a minute. The spec of the battery at the moment is 11.1v, 2200mAh and it lasts for 1 hour. On the net, I have found another battery with the spec 11.1V, 4400mAh which lasts for 2 hours. My current battery consists of 3 x 18650 3.7v, 2200mAh cells.

My question is, if I replace the 3 cells with 3 x 18650 3.7v, 2400mAh, will this give me a longer run time of the battery? Or is the battery set to only handle 2200mAh if you know what i mean?

Sorry its worded badly, but thats the easiest way of explaining it I could find.

Thanks in advance! :D
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Postby hikaru » Tue May 27, 2008 1:11 pm

As far as I know, the capacity is not hard-coded into the battery controller. So the 2400mAh-cells should work correctly.

But why do you do this experiment?
An upgrade of 200mAh will increase your battery runtime for less than 10 minutes (given, that the 2400mAh isn't a typo).
Running a modified battery comes with some serious risks.

Why don't you just get the whole 4400mAh-battery?
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Postby Jono-08 » Tue May 27, 2008 9:16 pm

Hi , thanks for the reply.

I was just using an example of the next capacity up that i could find of that particular cell. Also, i figured as my battery is already dead, i didnt have a lot to lose, and if it works, i've saved myself 70 quid. :wink: If not, ah well, i'll just buy the real thing.

And do you you speak from experience when you say it carries serious risks? (please dont take that the wrong way)

I've ordered 3 of the same spec cells that are already in the battery to do a straight forward swap over. I hope that this will work out ok when i rebuild it tomorrow.

Anyhoo, cheers!
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Postby hikaru » Tue May 27, 2008 9:58 pm

You have quite a lot to lose: Your notebook and maybe your health!

Have you ever seen a leaking battery? Lithium-ion batteries contain lithium-salts that react to hydrofluoric acid in contact with water. Normal air contains enough water for this reaction.
Or have you wondered why you shouldn't throw batteries into fire?
I have not seen something like this with a li-ion battery but I know similar scenarios with lead-acid batteries.

I admit it is unlikely that things like these will happen, but a short circuited battery can destroy much more than only the battery itself.
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Postby Jono-08 » Wed May 28, 2008 3:36 pm

Hey

I've done it, and its worked! 8)

I dont get the full hour, but to be honest, i wasn't really expecting it. I do get about 25mins though.

Thanks for your warning, but unfortunatly, i didnt read your last post until after i'd done it.

I am going to get a proper battery in the next couple of months though, just to be on the safe side, but i just need to save up a bit.

Anyhow, thanks mate :D
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