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Old 01-19-2009, 03:26 AM   #1
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Default Lipo race batt, how much mAh?

Hi I m new to electric touring scene, I m in a market of buying batts for my new sedan. I want a batt that can last 5 mins or more, thats the duration of races in my country. I ll be using EZrun 5.5T motor and will race it indoor as well as outdoor(on an asphalt track meant for nitro car). At the moment I m looking towards Intellect 3800mAh 35C and 5000mAh 30C. Hope you guys can point me to the right direction.

Thanks.
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Old 01-19-2009, 03:32 AM   #2
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Hi I m new to electric touring scene, I m in a market of buying batts for my new sedan. I want a batt that can last 5 mins or more, thats the duration of races in my country. I ll be using EZrun 5.5T motor and will race it indoor as well as outdoor(on an asphalt track meant for nitro car). At the moment I m looking towards Intellect 3800mAh 35C and 5000mAh 30C. Hope you guys can point me to the right direction.

Thanks.
IP3800 35C would be a minimum if you're running modified...

The C rating is adequate for the current draw (3.8*35=133A) and the capacity will be enough for a 5min race with a 5.5T brushless.

Personally I like to have some overhead, so I'd be happier with the 5000 30C (5*30=150A) packs from Intellect.

You've made a good choice with both those packs

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Old 01-19-2009, 03:39 AM   #3
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IP3800 35C would be a minimum if you're running modified...

The C rating is adequate for the current draw (3.8*35=133A) and the capacity will be enough for a 5min race with a 5.5T brushless.

Personally I like to have some overhead, so I'd be happier with the 5000 30C (5*30=150A) packs from Intellect.

You've made a good choice with both those packs

-Mark
Thanks for the info Mok.
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Old 01-19-2009, 04:11 AM   #4
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here's some figures for you from my experiences...

LRP 3.5T brushless, uses approx 2700-2900mAh indoors on carpet (short track 80m) geared around 12.6 FDR whereas at 10.5 FDR outdoors on asphalt (long track 250m) pulls around 3900-4100mAh.

the IP3800 25C packs I used initially didnt quite have the capacity (if it wasnt fully charged i might be 1 lap short of the 5mins) or the C rating to handle the LRP 3.5T brushless.. the packs heated up quite a lot and swelled slightly on their use, never vented or damaged the cells just swelled a little (90% sure this was the air expanding in the pack, not the cells)...

when i switched to the LRP 5300 28C packs (5.3*28=148.4A) i never had any heat issues with the packs and have always made the 5mins... this has ample overhead for the LRP 3.5T brushless - this would be much the same scenario with the IP5000 30C packs

to be honest, a 5.5T brushless and the IP3800 25C packs would be adequate for most tracks but i would consider this the limit for these packs.. the IP3800 35C packs would have ample overhead for the 5.5T and probably be adequate for a 3.5T brushless also..

but as i've said i like to play it safe with C rating and capacity, especially when running low FDRs on low wind brushless motors

IP5000 30C sounds like to way to go to me
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Old 01-19-2009, 04:51 AM   #5
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Just for info.. I run SMC4000 with 13.5BL in rubber sedan on carpet. We are pulling out about 2000mah-2500mah. That same motor in a 10th scale buggy pulled 1800-2200mah on a dusty loose track.


I think a 4000 is a good all round pack but would opt for a 5000 if your car can fit it. I did not want to shim my upper deck so passed on using 5000 for 4000 packs. The extra mah i think would be inportant in keeping the average voltage curve higher especially in mod, i think its probably beneficial in 13.5 as well just not as much
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Old 01-19-2009, 04:57 AM   #6
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Quote:
Originally Posted by mok View Post
here's some figures for you from my experiences...

LRP 3.5T brushless, uses approx 2700-2900mAh indoors on carpet (short track 80m) geared around 12.6 FDR whereas at 10.5 FDR outdoors on asphalt (long track 250m) pulls around 3900-4100mAh.

the IP3800 25C packs I used initially didnt quite have the capacity (if it wasnt fully charged i might be 1 lap short of the 5mins) or the C rating to handle the LRP 3.5T brushless.. the packs heated up quite a lot and swelled slightly on their use, never vented or damaged the cells just swelled a little (90% sure this was the air expanding in the pack, not the cells)...

when i switched to the LRP 5300 28C packs (5.3*28=148.4A) i never had any heat issues with the packs and have always made the 5mins... this has ample overhead for the LRP 3.5T brushless - this would be much the same scenario with the IP5000 30C packs

to be honest, a 5.5T brushless and the IP3800 25C packs would be adequate for most tracks but i would consider this the limit for these packs.. the IP3800 35C packs would have ample overhead for the 5.5T and probably be adequate for a 3.5T brushless also..

but as i've said i like to play it safe with C rating and capacity, especially when running low FDRs on low wind brushless motors

IP5000 30C sounds like to way to go to me
Yeah, thats what i thought after you post your first reply. I ll go with the 5000mAh.
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Old 01-19-2009, 05:00 AM   #7
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Originally Posted by Joel Lagace View Post
Just for info.. I run SMC4000 with 13.5BL in rubber sedan on carpet. We are pulling out about 2000mah-2500mah. That same motor in a 10th scale buggy pulled 1800-2200mah on a dusty loose track.


I think a 4000 is a good all round pack but would opt for a 5000 if your car can fit it. I did not want to shim my upper deck so passed on using 5000 for 4000 packs. The extra mah i think would be inportant in keeping the average voltage curve higher especially in mod, i think its probably beneficial in 13.5 as well just not as much
When you say you are pulling 2000-2500mah, how actually do you calculate this?
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