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Old 02-26-2012, 04:36 PM   #1
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hey, i need some help choosing lipo's for my cars. i have been getting together everything i need to start racing and am confused about what batteries to buy. My hobby shop races indoor carpet during the winter and alternates between onroad and offroad when the weather gets nice. Are $120+ batteries what I need? Can I use one battery for the day? Is discharge rate that important? and if so, what is a good rate to race with? Are there brands to stay away from? Are there any "best bang for the buck" batteries out there? My local shop tries to sell me the $125 "race packs" and I don't want to spend $500 on batteries. For what it's worth, these are the cars I have and plan to race; tc5 for RCGT, tc6 for stock touring, traxxas slashes for 2wd and 4wd short course. any help would be greatly appreciated.

ken
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Old 02-26-2012, 05:51 PM   #2
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If any of the classes have a "spec" battery then that is what you are stuck buying. Other wise check out hobbypartz and look into the roar approved gen ace packs. They hold up well and offer great bang for the buck.
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Old 02-26-2012, 06:13 PM   #3
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All you need is one pack per car. Throw it right back on the charger after your heat, and it should be good to go by the time the same heat is up. The C ratings are mostly marketing. 40C rated packs are great for anything except modified. The Gens Ace are great bang for the buck, when you can find them in stock.

For mere mortals, capacity is more important than C rating, especially for stock classes. As an example, in stock TC, I use about 2000mAh in 6 minutes, for an average current draw of 20A. Given that a 40C 5000mAh battery is supposed to be able to provide a continuous discharge rate of 200A, it's not a stretch to realize that the C rating really doesn't matter. The burst current rating of most Lipo batteries are usually 2x the continuous rating, or in this case 400A. Again, way more than required for stock. Also, 12 gauge wire is only rated to carry 60A, as are Deans connectors.

Get the brand you prefer if you don't want to risk the no-name brand.
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Old 02-26-2012, 06:31 PM   #4
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that's what i was looking for. i've gone on youtube and the gens ace batteries seem great, but i don't see them for sale anywhere? the price point is right on! So as a newbie, I shouldn't worry too much about discharge rate? it is more about capacity? That's really what I was looking for! Is there a minimum discharge rate I should go with? I see the 20C and 25C for cheap and then they get ridiculous as the rates go up.

thanks in advance
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Old 02-26-2012, 07:00 PM   #5
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One of the stock classes at Vegas either last year or the year before was won with a 28C rated pack. The theory is that for stock classes, a lower C rating is actually better since it causes the pack to heat up internally more during discharge, causing the pack to generate slightly more voltage.

Personally, I wouldn't go much below 30C rated packs, like the Gens Ace. RevTech, ThunderPower, SMC, Reedy, etc, all make decent packs. Find one in your budget that is in stock and you should be good to go. Just don't over discharge any of them, or you'll kill them prematurely (don't go below 6V for a 2 cell LiPo). Recharge them immediately after your heat. After the main, leave them until your next race day (you shouldn't store LiPos fully charged, either).
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