4s Batteries or 2s lipos with internal bullets in series
06-03-2013, 05:27 PM
#1
4s Batteries or 2s lipos with internal bullets in series
I was told by a few people that running two 2s lipos with internal bullets in series on an ebuggy with an RX8 1900 combo would get too hot and melt the pack and the connectors.
I have been running this setup on a larger track with pretty good size jumps for a few months now and havent really noticed any issues. The outside temps at the track can get up to 100 at times. So, I was wondering if this is a real issue and if I should make the switch to 4s lipos.
I have been running this setup on a larger track with pretty good size jumps for a few months now and havent really noticed any issues. The outside temps at the track can get up to 100 at times. So, I was wondering if this is a real issue and if I should make the switch to 4s lipos.
06-03-2013, 06:16 PM
#4
A lot depends on the quality of the connectors being used (and perhaps the soldering). Solid bullet style connectors are much better than spinning cage banana style.
I prefer a single 4S pack for simplicity, fewer connections and wires that might cause issues, perhaps easier to securely mount. Other than a saddle pack car of course, then the question isn't terribly relevant anyways.
Regardless if running 2 packs together it’s best to use identical packs purchased together and kept as a set. If not any capacity differences caused by different use, cycling, age, etc, can increase chances of running one pack too low.
I prefer a single 4S pack for simplicity, fewer connections and wires that might cause issues, perhaps easier to securely mount. Other than a saddle pack car of course, then the question isn't terribly relevant anyways.
Regardless if running 2 packs together it’s best to use identical packs purchased together and kept as a set. If not any capacity differences caused by different use, cycling, age, etc, can increase chances of running one pack too low.
Last edited by Dave H; 06-03-2013 at 06:34 PM. Reason: kant rite
06-03-2013, 06:34 PM
#5
I would use bullets most likey. maybe even the promatch packs with 5mm bullets.
http://www.promatchracing.com/prodde...od=CC720080CV8
http://www.promatchracing.com/prodde...od=CC720080CV8
06-03-2013, 06:59 PM
#6
can't even mount a 4S in the car if you wanted to.
There are many more advantages to doing it that way.
06-04-2013, 01:35 PM
#9
However, I've recently switched over to 2s x 2s shorty packs due to the weight savings and variable weight distribution they offer, which is working out great! Most 4s packs on the market are way over weight(too many maH) and too big/tall for most bodies (with the exception of the newer 3500-4300 protek packs). I don't need 5000 or 6000+ mah batteries, I can run 10 minute mains on 4300mah every time. Now only if they offered 4s 4000-4500maH shorty packs!
06-04-2013, 01:54 PM
#11
I see no reason to buy 4S packs, you can use your 2x2S packs if you race in any form of 1:10th. The only reason would be the price, but they aren't cheaper at all then 2x2S packs. I have always ran 2x2S (with bullets) and I never had overheating or melting issues nor have I ever heard of this. Furthermore, with 4S if one cell is bad the whole pack is gone while with 2x2 setup if one battery is bad you only need to replace that one. So to put is simply, go with 2 packs, especially if you have any 1:10th car 
06-04-2013, 02:03 PM
#12
I see no reason to buy 4S packs, you can use your 2x2S packs if you race in any form of 1:10th. The only reason would be the price, but they aren't cheaper at all then 2x2S packs. I have always ran 2x2S (with bullets) and I never had overheating or melting issues nor have I ever heard of this. Furthermore, with 4S if one cell is bad the whole pack is gone while with 2x2 setup if one battery is bad you only need to replace that one. So to put is simply, go with 2 packs, especially if you have any 1:10th car
06-04-2013, 02:07 PM
#13
In my 1/8 truggy, i run 4S packs only. I did use a couple of 2S packs in series a couple times but i never felt comfortable doing it, not sure why. When you have a single tray, why use two different batteries? Maybe that was my logic behind it lol...
06-04-2013, 02:09 PM
#14
I was told by a few people that running two 2s lipos with internal bullets in series on an ebuggy with an RX8 1900 combo would get too hot and melt the pack and the connectors.
I have been running this setup on a larger track with pretty good size jumps for a few months now and havent really noticed any issues. The outside temps at the track can get up to 100 at times. So, I was wondering if this is a real issue and if I should make the switch to 4s lipos.
I have been running this setup on a larger track with pretty good size jumps for a few months now and havent really noticed any issues. The outside temps at the track can get up to 100 at times. So, I was wondering if this is a real issue and if I should make the switch to 4s lipos.
Over time, internal bullets are a hazard because they will wear and they will not make as good of a connection. It is true that Deans will wear, but they are not attached directly to the battery tabs where additional heat can be a problem.
06-04-2013, 02:53 PM
#15
This is a really dumb idea. If you have many cycles on a set of 2s packs and one dies, then putting a brand new pack with an older pack is asking for problems. Also, if you are running 2x2s packs in a 1/8th, you shouldn't be using these packs for other applications. You should treat them as a 4S pack and always use them together.