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Old 08-05-2008, 09:58 PM   #1
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Hey guys,

I'm still just getting my feet wet really in this whole RC business. I got my first stock RC car about a year ago (Tamiya Mini Cooper). I really wanted to try racing off-road so I finally broke down and ordered a Associated B4, Mamba Max 5700, a lipo charger, and a cheap Lipo battery to try out from hobbycity.com about a month ago. Up until that point all my electric cars were 100% stock (motor system and batteries), thus very slow. So I'm just entering the world of brushless/Lipo. Anyway, the stuff is finally getting here...

I got the Lipo battery today. It's a Zippy-K 4300mAh 2S1P 20-30C. I got it for $40 plus $10 shipping, and for that price, I thought it was worth trying out, even if I risk getting a crappy battery. The Zippy-K 4300 was the only 2S battery they had that's over 3000 mah, so I didn't have much choice when ordering it.

Anyway, I might've gotten a bit careless because I've seen some photos of Zippy packs in similar buggies and such, and they had no problems fitting in the battery tray even with those THICK 10AWG wires from the battery.

That wasn't the case for me. =(

I didn't really pay much attention to the size when ordering, but it says 145x45x18mm on their site. The battery tray length in B4 is just about 145mm, or just under it. The battery, however, is only 145-146mm at its shortest side. The other side is much longer. In fact, all the dimensions are only valid if you measure at their absolute lowest point.

Anyway, the pics show my problem better than I can explain it.







So,

Any advice on what I should do?

I don't really wanna sell it or trade it, cuz I've tested the cells' voltage and its exactly 3.86v for both (perfect storage voltage, and in balance), so it seems like I didn't get a bad cell or anything. If I get another pack from HC I might not be as lucky again.

I think the best solution at this point would probably be to take the pack apart, replace those HUGE 10AWG wires with something thinner (I doubt it really needs 10AWG, it's only 2S * 4300 mAh * 20C discharge)... And see if that shortens its length a bit. However, like I said before, I'm pretty new to Lipo... I'm not really good at soldering (planning to get better though, just don't wanna start off learning on a Lipo bomb lol), and after watching so many Lipo explosion vids and not having much experience with them, I'm very scared of it blowing up lol... So I'm not sure if this is possible for me atm.

Another possible solution would be to try and think of a way to mount the pack so that it's not fully inside the tray, but rather sort of laying on the bottom of the servo, sticking out... But then I gotta make sure it doesn't come out flying if I happen to have a hard crash... :/ Don't think it's the best idea.

Help, plz!
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Old 08-05-2008, 10:03 PM   #2
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Put thinner wires on the battery and if it still doesn't fit I would sell it and get a new battery.
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Old 08-05-2008, 10:33 PM   #3
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I wouldn`t put thinner wires on it . The battery manufacture put 10 guage wire on there for a reason , to handle the amp draw . Going thinner will cause the wire to heat up faster and most likely not but possibly burn the wires and short the battery . I`d return it or sell it .
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Old 08-06-2008, 05:31 AM   #4
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Originally Posted by Briguy View Post
I wouldn`t put thinner wires on it . The battery manufacture put 10 guage wire on there for a reason , to handle the amp draw . Going thinner will cause the wire to heat up faster and most likely not but possibly burn the wires and short the battery . I`d return it or sell it .
Very true. Dont EVER put thinner wires on a lipo. Or dont even mess with the wires PERIOD. You could never get as good of a solder point like they did from the factory so just dont touch it. Theres quite a market for used lipos so just sell it. But do a little research before you buy your next one.
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Old 08-06-2008, 07:09 AM   #5
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I wouldn`t put thinner wires on it . The battery manufacture put 10 guage wire on there for a reason , to handle the amp draw . Going thinner will cause the wire to heat up faster and most likely not but possibly burn the wires and short the battery . I`d return it or sell it .
Well, the Mamba Max ESC uses 13 AWG wires to connect to the battery, as far as I know.

Also, even the most high quality packs like TrakPower 4900 or Team Orion stuff use 12-13 AWG wires from what I can see. I really doubt this 4300 mAh 20C discharge battery *REALLY* needs 10 AWG. I'd bet the main reason they used is to make it *seem* like a pack that's capable of higher discharging... So 10 AWG is probably overkill. 12-13 would likely be more appropriate.

The 3000 mAh 20C Zippy-K pack uses 10 AWG too. There's just no way it absolutely needs that much, when even the 30C packs use thinner wires.

I'm just guessing though, and I wouldn't mess with wires unless I was 100% sure of what I was doing.
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Old 08-06-2008, 07:39 AM   #6
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Any advice on what I should do?p
Yup, next time don't order a battery as a way to save a buck or without knowing it will fit.
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Old 08-06-2008, 08:29 AM   #7
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shurcooL, a battery that doesn't fit is a battery that is no good. Sometimes when you cut corners this happens and it has happened to all of us at one time or another. I would personally buy either trakpower, orion, maxamps, or some of the other brands that have specifically made their cells to fit these types of 1/10 scale cars. Let me know if you need any help.


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Old 08-06-2008, 10:10 AM   #8
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Quote:
Originally Posted by shurcooL View Post
I didn't really pay much attention to the size when ordering, but it says 145x45x18mm on their site. The battery tray length in B4 is just about 145mm, or just under it. The battery, however, is only 145-146mm at its shortest side. The other side is much longer. In fact, all the dimensions are only valid if you measure at their absolute lowest point.
Send it back and tell them to send you a battery with the measurements that they advertised. Measurements shouldn't be the smallest point of a dimension, it should be the largest. Tell them to make it right or refund your money - no reason to take a loss on selling it used when you haven't used it.
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Old 08-06-2008, 11:15 AM   #9
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Thanks for advice Miller, but you can't expect that kind of service from a chinese supplier. They're already selling things for 1/3rd the price you'll see anywhere else.

Anyhow, I don't think I should take a loss at this. The battery is in demand and I'm sure it's great for other applications, such as helis/planes/boats where the dimension requirements are not as strict. It's already out of stock at HC atm and they get picked up fast. Plus, someone buying it from me would have the advantage to know that it's not a DOA, as I've checked the voltage and can confirm it's in good shape - no bad cells; something you always risk when buying from HC, as you can see from the comments. Not to mention the faster/cheaper shipping from Canada... Not sure on that last one, unless it's a local buyer.

Anyway, I'm not selling it just yet as I really wanna see if there's anything I can do with it... I really don't wanna let it go. >.<

I could always buy another and make a 4s pack out of it for my future 8ight conversion, although I'd prefer to get a separate 4s battery for that so I have only one balance port to deal with. It'll fit in Dan's RCPD battery holder (which is 170mm long) w/o problems.
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