Author Topic: 7.4v Lipo batt for testing  (Read 232 times)

Offline Joolstacho

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7.4v Lipo batt for testing
« on: 13.11. 2020 02:31 »
Is there any problem with using a 2-cell 7.4 volt LiPo battery for 'static' testing my rewired 6v system?
I realise there are issues regarding charging using LiPos, but can I use one just to test the circuit?
(I'm going to do it anyway!!! What could go wrong?)   *help*

Offline RDfella

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Re: 7.4v Lipo batt for testing
« Reply #1 on: 13.11. 2020 11:59 »
Can't see one, apart from the massive current they can put out so beware short-circuits!
'49 B31, '49 M21, '53 DOT, '58 Flash, '00 Firestorm, Weslake sprint bike.

Online Greybeard

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Re: 7.4v Lipo batt for testing
« Reply #2 on: 13.11. 2020 13:34 »
I was reading about LiPo batteries. Seems if one catches fire there is no way to stop it burning as it generates its own oxygen. Even dropping it in water would not extinguish it. The advice is to charge them outside in fresh air and never leave them alone while charging. Be very careful not to damage the battery as that may cause it to catch fire.

Offline Joolstacho

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Re: 7.4v Lipo batt for testing
« Reply #3 on: 13.11. 2020 22:17 »
Yes thanks mate, I've been using LiPos for many years for RC stuff so I'm aware of the safety issues.  *wink2*

Online Greybeard

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Re: 7.4v Lipo batt for testing
« Reply #4 on: 13.11. 2020 22:36 »
Yes thanks mate, I've been using LiPos for many years for RC stuff so I'm aware of the safety issues.  *wink2*
Not everyone will know though. I read that warning about LiPo's because of my new interest in electric RC aeroplanes

Offline trevinoz

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Re: 7.4v Lipo batt for testing
« Reply #5 on: 13.11. 2020 23:08 »
A battery charger does a good job, if you have one.

Offline Joolstacho

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Re: 7.4v Lipo batt for testing
« Reply #6 on: 13.11. 2020 23:21 »
Right GB, it's as well to warn people. I've been using Lipos ever since they became available.
I do take sensible precautions, but there's no need to be paranoid about it. I always unplug them after using.

Shorting out the terminals or puncturing the cells kills 'em quickly and have been known to fire them up - literally.
In (what, must be about 15-20 years using them), I've punctured one accidentally, it didn't flame, but got VERY hot and exuded some rather pretty smoke.
Out of the dozens I've used, I've had a couple that inflated a bit, and a few that lost their girlish laughter for no apparent reason.

You need a good charger, one that's made for the job, (Lipos) but they're cheap enough nowadays. Lipos are very sensitive to charge rates etc, so you can't just use a car-type charger that's made for for lead acid batteries. Oh, and overdischarging them will kill them.