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Bad lipo cell voltages after track?

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Old 03-17-2010, 11:42 AM
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c6z06
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Default Bad lipo cell voltages after track?

I drove my vorza yesterday for some 80mph runs, only got around 70-75mph and then today I drove it on the track (went back to 52mph gearing) for 30 minutes on the same charge. Cell voltages after charge were all 4.16-4.20v. After the runs the cells were as follows:

3.54 3.19 3.63

3.64 3.65 3.42

Now I'm fine with all the cells being between 3.42v and 3.63v but that 3.19v worries me. Is this rare or everybody's lipo packs are around there after 35-40 minutes runtime. Thanks.
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Old 03-17-2010, 02:11 PM
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Default RE: Bad lipo cell voltages after track?


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ORIGINAL: c6z06
Is this rare or everybody's lipo packs are around there after 35-40 minutes runtime. Thanks.
everybody's pack's cell voltages will be at totally different voltages after 35-40 mins of runtime, even if it is the same vehicle.

the 3.19 does seem a little low, maybe stop your runs at 30 mins and make sure you balance charge your packs really well, that middle cell might be just a little weaker than the rest.
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Old 03-17-2010, 02:36 PM
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Default RE: Bad lipo cell voltages after track?

Here is the question do you balance your packs before and after every charge? I have had some of my packs drop as low as 3.05 and 3.10.
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Old 03-17-2010, 03:52 PM
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Default RE: Bad lipo cell voltages after track?

you balance them while you charge them. Does your charger have a balance port? If not you have to get a cell balancer that plugs into your balance tap on your battery while you charge.
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Old 03-17-2010, 05:13 PM
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Default RE: Bad lipo cell voltages after track?

cell 2 will always be that way since it is the smallest capacity (as long as it wasn't the lowest at start)

normally never balance before the charge since charging in series will "bring the cells into balance" and therefore balancing discharged cells would be counter-productive.
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