a123s or lipo? again....

[t-maxxracer32]

hey guys iam at the point to where i can buy my batteries and i want to make sure im making the right decision.

one of the other members said there was a deal at amazon for 105 per 36v battery with free shipping. so that means i can buy 3 of the batteries for the same price i would be spending on the evo 30s i was planning on buying.

there is a thread on rcgroups on how to build the pack without buying any other peices.

so it would be 315 flat for 5 6s packs.

with the lipos it would be 300 for one 5s 5ah pack.

which means if i got the lipos the i would have one battery that lasts for about 30 minutes ORRRRRRR each a123 pack would last for about 5-10 minutes... dont really know exactly.

so the least amount of runtime out of all the a123 packs would be 25 minutes... but it could go for as long as 50 minutes.

with the a123s i could charge them extrememly fast too im sure. im guessing around 20-30 minutes per pack?

if i built a 6s configuration it would weigh aproxx 1lb. im sure thats about the same as the 5s lipo right?

only real downside i can think of with the a123s is that i personally have to build the packs. which is good and bad at the same time. i liek soldering stuff and building my own stuff, but i dont want to mess anything up.

a plus with the a123s is that they will put out more power than the lipos... they will be pushin 30c's at 19.8V correct?

wheras the lipo will be 30c at 18.5v i beleive.

only thing i think i might have to worry about is the A123s heating up.. idk if they will... idk anything about them really.

can anyone enlighten me about this?

ive asked questions before and had this exact same thread a while ago but now i am actually going to buy them.

also i have a truck ready for them.

thanks alot!

[MetalMan]

A123s can be charged and discharged faster than Lipo with fewer problems, because they are more resilient to overcharge/overdischarge.
A123s can do many more cycles than Lipo packs, and over time instead of losing both capacity and power output, they only lose capacity.
As you noticed, A123s are super cheap.
A123s are far more durable.
A123s are a bit heavier.
At 30C, an A123 cell will be at about 2.1-2.2v (6s1p A123 @ 30C will drop down to about 13.2v, I'd go with 2p).
I like to think that each A123 cell is good for about 200watts in peaks.
A123s don't have much of an issue with heat (none of mine have).
I just bought my fourth Dewalt 36v pack through Amazon ($105 shipped is a steal!).

[t-maxxracer32]

maybe someoen can come in here that really likes lipos and do a rebuttle

where is aqwut at? lol

[aqwut]

Originally Posted by t-maxxracer32

maybe someoen can come in here that really likes lipos and do a rebuttle

where is aqwut at? lol

Hey..! rebuttle not needed... I like them both...
What I like about Lipos..
more capacity, good discharge(25-30C), good charge rate(2C), good price (for me anyways)..
What I don't like..
Too sensitive to physical damage..

What I like about A123
Awesome charge rate (3-4C)/discharge rate (30C), good price($90 of ebay), able to take a physical beating.

What I don't like about A123
low capacity, and awkward shape.

The weights of bother me too much..

Those are my thoughts.. but I love them both.. I have a hard time choosing, so I just buy both... but my decision leans towards lipos..
If you decide to get lipos... P.M. me.. I can get you a good price...

[BP-Revo]

Lipo's are lighter
Lipo's have more voltage
Lipo's have much more current capability (there are Lipo's which can do 30C and hold ~3.3v per cell). Thats a .4v drop off nominal, while a A123 drops ~1.4v off nominal.


I personally like Lipo. Sure it takes a bit more attention since they aren't as "solid" as an A123 pack in terms of safety, but really its as simple as following a few simple guidelines. You can actually get a NiMH cell to explode with a "BOOM" to it if you overcharge it...I've experienced it twice (was at the track when someone made the mistake).

[t-maxxracer32]

well i just like the fact that i can get 5 packs for the price of 1 lipo...

it will be fun building them too. the way i see it is im getting either 2 6s2p packs and 1 6s1p or 5 6s packs.

plus if i do a 6s2p configuration it will balance the truck out a bit more im sure.

idk.

[cart213]

I just bought a dewalt pack myself. I've already got three 2s2p packs. I'm planning to make the new pack 5s2p. For me, it's all about the safety. I'm not real careful with my batteries, so I like knowing that I can leave them in my hot car in the summer without worry, and that I can charge them and not stand over them the whole time.

[tashpop]

i'm a fan of lipo because of their size and weight to power ratio, but since i've jumped on the a123 bandwagon, i'm hooked. before you would really have to budget a project to afford the batteries, but not really with the a123's. another benefit that i really like is that even though you take up more room per power with the a123's than lipo, you still get more mounting options for these custom builds because of the individual cells. i have some very different looking 6cell packs i'm making for my flm emaxx. and i also used a pair (shot gun) of 4s1p's on my ls10 project.

[sl1]

Hello all,
I am in the process of building a brushless CEN Matrix TR so I bought 2 dewalt 36v packs. I called A123 yesterday and talked to Brian and he said that he is getting 21min out of a 6S1P battery in an 8ight with a
Neu 1515-1Y and a MM combo on the track that tops out at 45mph. The amp draw peak was 40A in the 21min on the track. So I can't decide weather to try a 5S1P or a 5S2P in the truggy I figure that 30mph is fast enough for the track.

[zeropointbug]

Originally Posted by sl1

Hello all,
I am in the process of building a brushless CEN Matrix TR so I bought 2 dewalt 36v packs. I called A123 yesterday and talked to Brian and he said that he is getting 21min out of a 6S1P battery in an 8ight with a
Neu 1515-1Y and a MM combo on the track that tops out at 45mph. The amp draw peak was 40A in the 21min on the track. So I can't decide weather to try a 5S1P or a 5S2P in the truggy I figure that 30mph is fast enough for the track.

Yeah, 6s1p SHOULD allow the same power output as a 5s2p in a given vehicle, and a given motor choice... because the 6s1p will have higher voltage drop.

Right now, I am running a 7s1p pack in my Revo on Neu 1512, and I love it, it's light, it's powerful (~equivalent to 5.5s flightpower lipo), it has 15 min runtime, and i can charge the pack up in another 15 mins, it's great.

Tmaxxracer32... just go with A123's man and be done with it, enough of this.

[t-maxxracer32]

ya 30mph on a track is a reasonable speed.

you might want more if its a big wide open track but even then.

if you cant control it at 30 then why would you want anymorE!?!?

[BL_RV0]

id go with the trueRC lipo packs or the hextronic lipo packs. cheap, durable, and i personally love the blue wrap on the hextronics!

[t-maxxracer32]

i do have a true-rc pack right now and all i would have to buy is a 2s pack... but the only thing is that if i decide to get a123s how am i going to mount them? they are completely diff than the lipos... idk as usual.

pmed you aqwut!

[ClodMaxx]

i have a123s now, and it's fine for bashing in both my stealth and the upcoming eXT8. but once i start getting into racing, i'll pick up lipos... much less weight. the a123's are awesome for all the reasons already listed, though. SUPER fast charging and stupid-safe, which i need.

[t-maxxracer32]

ya if i get a123s i will use them primarily for times when im going to be stupid with my truck.

i might pick up 1 of these things and make 2 5s packs and call it good.

when i want to drive it dumb and mess around ill bust these out!!

thanks alot for your input.