Lipos

DeputyDad78 · 11-01-2009, 06:42 PM

I'm very new to this and have been reading up on alot of info and still confused lol. So I have some questions..

1. How often can you recharge Lipos.

2. there only a certain amount on cycles a lipo has?

3. 3s 2s 20c 30c What is all that....

4. I don't race just bash and would like a battery that lasts a good while. Setup will be Traxxas velineon setup.

I read about the cutoffs, charging/discharging so I'm ok with all that I think. If theres a link please post it for me.

Thanks for the info

flame56mx · 11-01-2009, 07:13 PM

Quote:

Originally Posted by DeputyDad78

I'm very new to this and have been reading up on alot of info and still confused lol. So I have some questions..

1. How often can you recharge Lipos.
repeatedly, I recharge almost after every heat/race if necessary

2. there only a certain amount on cycles a lipo has?
?? supposedly more charges in them than nimh, but I haven't got to the end of one yet

3. 3s 2s 20c 30c What is all that....
2s,3s is the amount of cells, a 2s has 2 cells and so on. 20c,30c is the discharge rate, how much power it can discharge at, so a 35 c will provide more power than a 20c

4. I don't race just bash and would like a battery that lasts a good while. Setup will be Traxxas velineon setup.
anything around 3400 or more will suffice, a 5000 will give more run time

I read about the cutoffs, charging/discharging so I'm ok with all that I think. If theres a link please post it for me.
Lipo can be very dangerous, so always make sure you have a lipo cutoff,and eliminate any distractions before you charge, making sure you dont charge at the wrong rate---booom--then flames..

Thanks for the info

No problem

Duster_360 · 11-01-2009, 07:22 PM

1. As many times as you want.

2. 300 is quoted sometimes, I'm into a pr well over 100, but don't really know

3. C is a discharge rating and is also used to spec charging. A 2S 5000mah 30C lipo is able to produce a continuous discharge of 5000/1000 x 30 = 150amps. An 8000 15C lipo would be able to discharge 8000/1000 x 15 = 120amps. Its a function of the C rating and the capacity of the lipo. Its alos used in chargibng - a 1C charge for the 1st example above would be 5000/1000 = 5amps. A 2C would be 5000/1000 x 2 = 10amps. A 3C charge rate would be 5000/1000 x 3 = 15amps. Lipo manufacturers will tell you (usually on label) what they advice for charging. If not specified, stick with
1C.

4. A 5000mah with 20 - 30C would be a long lasting lipo with plenty of punch.

5. I'll check, theres a good one on a heli site and i'll have to find it. Here it is found it -

http://www.rchelicopterfun.com/rc-lipo-batteries.html

DeputyDad78 · 11-04-2009, 04:53 PM

Now do some esc limit the amount (15C,20C,30C ect) that they can handle? Same with motors? And what would a good charger for someone totally new to Lipos? I have seen some that auto adjust to cells,voltage ect

Duster_360 · 11-04-2009, 07:38 PM

No, its the motor, not the esc that determines amp draw. After than your setup (size, weight and gearing) also affects amp draw.

Chargers come in all sizes and prices. Prob be good to get a AC/DC powered charger since won't have to buy a separate power supply. If you're just doing 2S lipos, Triton2 is a good balancing charger. Hyperion 0606i is also a good AC/DC balancing charger.

http://www3.towerhobbies.com/cgi-bin...&I=LXVRS6&P=ML

http://www.allerc.com/product_info.p...oducts_id=3367

There are others.

OTE_TheMissile · 11-04-2009, 07:43 PM

For $80, my DuraTrax Onyx 230 is an awesome little charger. AC/DC, charges pretty much every chemistry known to man, and fairly simple to set up and use.

http://www3.towerhobbies.com/cgi-bin...&I=LXTCK1&P=ML

DeputyDad78 · 11-04-2009, 07:54 PM

Does it charge LiFe also?

OTE_TheMissile · 11-04-2009, 08:12 PM

~runs to basement shop & grabs box~

1 to 8 nickel cells (NiCd/NiMH)
1 to 3 cells-in-series lithium (LiPo, Li-Ion, and yes, LiFe)

Fast-charge current: .1 to 7A (lithiums limited to 2C)
Fast-charge termination: Peak detect for nickels, CC/CV for lithiums

10 battery memory to tailor charging setups to each pack. I've got one profile set to charge my TrakPower 4900mAh 2S1P LiPos, one profile for the 4-cell NiMH packs that go in my Legends car, and one for my buddy's 7-cell NiMH packs if he needs to use my charger.

DeputyDad78 · 11-04-2009, 08:20 PM

Thanks! Hafta look into that

Duster_360 · 11-05-2009, 03:50 AM

It will need a separate balancer.......reason for the price diff...

OTE_TheMissile · 11-05-2009, 09:18 AM

If you're of the opinion that a balancer is a necessity, anyway. I still see opinions on balancing run the gamut. Battery manufacturers say you need to balance every time (usually followed by a link to buy THEIR balancer

), a lot of weekly racers I've talked to say they balance about once a month, and then there's guys that've put a year of running on their LiPo without balancing once and had no issues whatsoever.

That being said I admit I use a balancer, a TrakPower V-Balance, but I got it mostly because I had the extra $30 on me at the time and chargers with built-in balancers just didn't look good for me (DC only, monolithic menu system, additional features I'll never use, goofy stock connectors, etc. etc.). I balance every time just out of convenience; I have the thing, so I might as well use it. But I've got no problem charging a pack with just the charger.