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Old 06-25-2008, 08:32 AM   #1
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Default Lipo question.

When I charge a lipo pack do I always need to balance it?
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Old 06-25-2008, 09:54 AM   #2
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You do not have to balance it but it does add a level of safety. If you can balance while charging why not use it?
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Old 06-25-2008, 10:45 AM   #3
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i have a question too. in the cars and trucks do you have to use the lipo's with the hard pack? i don't have a lipo battery or charger but i'm goona stop and get them when i get off work today. thanks.
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Old 06-25-2008, 11:48 AM   #4
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Quote:
Originally Posted by stalk View Post
i have a question too. in the cars and trucks do you have to use the lipo's with the hard pack? i don't have a lipo battery or charger but i'm goona stop and get them when i get off work today. thanks.
Have to nope, but it is a good idea. It's there to protect the cells as well as the vehicle.
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Old 06-25-2008, 01:17 PM   #5
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can you explain a little more? protect the cells and car from what? i know that sounds like a smart tail but i couldn't figure out another way to say it. thanks.
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Old 06-25-2008, 01:42 PM   #6
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The hard case is mainly to prevent damage to the battery. If a lipo is punctured or such, say from a crash, bad things happen. It can burst into flames from the resulting internal short. What is fondly known as a "thermal event".

Hard cases are required by ROAR for racing, but not all local tracks require them. Highly recommended for all RC in my opinion. As always your mileage may vary.
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Old 06-25-2008, 05:13 PM   #7
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The lipo cells are soft and can be punctured easily. The hard case protects the cells and it is a good idea to have a pack with a hard case.

I lost a GTB and damaged my buggy because of a soft pack lipo fire.
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Old 06-25-2008, 07:31 PM   #8
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Guys please rember that I started the thred and even though it was a good question I would still like more replys.
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Old 06-25-2008, 07:51 PM   #9
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You probably haven't had more responses because OG hit the nail on the head.

+1 for OG's post.

Any more takers?
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Old 06-25-2008, 08:09 PM   #10
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Quote:
Originally Posted by MRorange View Post
When I charge a lipo pack do I always need to balance it?
If you run the pack down to 80% discharged you should balance the pack after a few runs. The quaility packs ie: kokam,enerland don't seem to require balancing as much as the cheaper packs do.

Quote:
Originally Posted by stalk View Post
i have a question too. in the cars and trucks do you have to use the lipo's with the hard pack? i don't have a lipo battery or charger but i'm goona stop and get them when i get off work today. thanks.
The case does protect the cells better than no case.If you plan to race most tracks will want you using hard cased lipos.
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Old 06-25-2008, 08:31 PM   #11
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If I dont ballance will it cause damage to the pack? And what happens when you ballance?
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Old 06-25-2008, 10:32 PM   #12
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Quote:
Originally Posted by MRorange View Post
If I dont ballance will it cause damage to the pack? And what happens when you ballance?

Lots of us take it for granted but the first thing to understand is that almost all batteries are made up of a group of cells. Due to manufaturing tolerances every cell is slightly differant. Even though they may be labeled 4000mah, that should just be the min. In reality they may range from 4000mah to 4200mah. Of course when charging, the higher capacity cell will take longer to charge and will cause the charger to over charge the other cell or cells. In most other battery styles (NiMH, NicD) the cells are tolerant of a slight overcharge but lipos are not.

manufacturers try to keep tolerances close and group cells together by capacity to keep the differance between cells small but at some point the cells will become out of balance (Not the same voltage) and everytime you charge and discharge it will do slight damage to the out of balance cell. In time that damage will get worse and cause a cell to fail. Lots of time they just puff up but if you don't catch the failure it can cause a fire.


The balancer serves 2 purposes.

1. It will terminate the charge if any one cell reaches to high a voltage (Over charges)
2. It will hold back or slightly discharge the cell that is higher in voltage keeping alll the cells "Balanced"

Hope some of this helps.


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Old 06-26-2008, 06:33 AM   #13
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Check the voltage of each cell as they approach full charge. They should not go above 4.2 volts, I believe that the absolute limit is in the 4.22 to 4.25v range. If the cells are the same or at least within a few hundredths of a volt you’re good to go. If off much it needs balancing.
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Old 06-26-2008, 08:48 AM   #14
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What if I only charge it to 4500mah (It is a 5000mah lipo) Would that work?
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Old 06-26-2008, 10:15 AM   #15
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why not just invest 40 bucks into a balancer, it is well worth it and will keep you and others safe. The commonsense blinkies are a good and cheap balancer, now they have a balance pro that also shows the voltage of each cell. check it out.

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