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Old 04-05-2012, 01:54 AM   #1
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Default Battery question (charging and how run Li-Po in series)

Hi,
looking for some help, my Venom Pro charger manual advises never to charge a Li-Po over 1C charge rate but the Venom 7.4V 2S battery I have, has on it that the charge rate is 3C?

Also how do you run lipo batteries in series?

I have a 1/8 buggy and I want to use 2 x 2S batteries instead of a 4S. I've read that you cun run them in series e.g. one lead going from -ve to -ve and teh +ve go to the deans connector. Not sure how this is done as I would prefer not to use a "Y" harness. The batteries have the +ve and -ve round holes that you plug the leads into.

Thanks!
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Last edited by Taman; 04-05-2012 at 02:10 AM.
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Old 04-05-2012, 07:23 AM   #2
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Quote:
Originally Posted by Taman View Post
Hi,
looking for some help, my Venom Pro charger manual advises never to charge a Li-Po over 1C charge rate but the Venom 7.4V 2S battery I have, has on it that the charge rate is 3C?

Also how do you run lipo batteries in series?

I have a 1/8 buggy and I want to use 2 x 2S batteries instead of a 4S. I've read that you cun run them in series e.g. one lead going from -ve to -ve and teh +ve go to the deans connector. Not sure how this is done as I would prefer not to use a "Y" harness. The batteries have the +ve and -ve round holes that you plug the leads into.

Thanks!
For safety reasons you should not charge over 1C. This is not to say that the battery in question won't take a 3C charge, but again it's for safety concerns.

To run batteries in "series" the + on the connector goes to the + on one pack. Then you take the - on the connector and it goes to the - on the other pack. Then what is left is a wire from the first packs - to the second packs +. This is "series" wiring. This increases the voltage (in this case double) and retains the same mAh.

Two 7.4v / 5000mAh packs in "series" will become 14.8v / 5000mAh

Two 7.4v / 5000mAh packs in "parallel" will become 7.4v / 10000mAh

Also make sure that you ALWAYS balance charge each battery separately.


Hope that helps.
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Old 04-05-2012, 01:55 PM   #3
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Thanks for the reply, appreciate it.

So can I wire it up to use only 1 plug as per my picture below? I think I have seen it done this way. The white line is just meant to represent the wire.
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Last edited by Taman; 04-05-2012 at 04:43 PM.
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Old 04-09-2012, 06:07 AM   #4
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Originally Posted by Taman View Post
Thanks for the reply, appreciate it.

So can I wire it up to use only 1 plug as per my picture below? I think I have seen it done this way. The white line is just meant to represent the wire.
Yes. That is "series" wiring.
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Old 04-14-2012, 03:01 PM   #5
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Since I will be using these packs with a 1/8 tekin rx8, is there a certain guage of wire I should be using eg 8 AGW? thanks
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Old 04-15-2012, 07:13 AM   #6
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12 guage (AWG) is usually enough.
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Old 04-15-2012, 08:11 AM   #7
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Make/buy a Y harness, then you can use the 2s packs in other cars as needed. If one pack goes bad you dont need to solder up anything else. Plus if you ever leave 1/8 scale you can still sell the packs individually.
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Old 04-15-2012, 08:23 AM   #8
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Other than it’s a good idea to treat the 2 packs as a single pack throughout from new. If they differ any including due to different usage history one runs the risk of having one pack dump before the other, which may not be caught by the low voltage cutoff in time.

If you do use them independently, or replace just one, recommend being extra careful with run time, maybe use a higher LVC setting, etc.
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Old 04-15-2012, 09:04 AM   #9
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I use this and works very well:
http://shop.ehobbyasia.com/gt-power-...s-adapter.html
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Old 04-20-2012, 09:45 AM   #10
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It used to be recommended that batteries not be charged above 1c because that is all they would handle. now they are making batteries with a much higher "c" rating and the improved technology is allowing them to be charged at a higher rate. in the case of some batteries, up to 10c or higher. i have had no issues yet charging my batteries at 3c (15 amps) as they state they can be charged at 5c, and 8c respectively.
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