Lithium battery packs

[RockyD]

Is anyone out there experimenting with Lithium batteries? If so are there any other drawbacks besides the high cost? I am just starting my first RC Crawler (a TXT-1) and wonder if Lithium batteries would give you longer run times as well as more power.

Any comments on the best types and brands of batteries for crawling would be appreciated.

 

[kevinlongisland]

the main disadvantage of lithium polymer packs is that they are dangerous and they are not durable. the outside shell is a thin metal that is easy to puncture. here is what happens if you don't charge them right:

http://www.rcstuff.us/battery/lipo/images/LipoFire.wmv
http://www.rcstuff.us/battery/lipo/images/LipoFire.mpg
http://www.rcstuff.us/battery/lipo/lipo_DNA.html

the best thing is to just stick with regular electric r/c car/truck batteries. most people like the high amp/hour packs, like the 3000mAh packs. i personally buy the cheap shark packs from tower hobbies. you can get 12 packs for $99. it's a great deal and they work just fine for crawling.

 

[Gimbal]

$99 8O that's a killer deal! ...might have to check that out...

 

[simtechray]

I run 8000mah Li-po's, I'll never go back to nimh.
Advantage: Higher voltage, better run time, lower weight.
Drawbacks: Need a li-po charger, cost, not as durable.
Some of the fire videos you see on the web are people trying to make them catch on fire, ie charging at double capacity and such. If treated properly such things don't normally happen. If your going lithium, get lithium polymer not lithium ion.

 

[RockyD]

SimTechRay,
Where/how did you get the 8000 mAh setup? I have only been able to find 3000 mAh maximum packages and combining them would seem to be a rather large package for my TXT-1.

 

[kevinlongisland]

rockd, the airplane guys are really the ones that use lipoly technology more than anyone else. go to rcgroups.com and you will find all the info you need:

http://www.rcgroups.com/forums/forumdisplay.php?f=129

 

[simtechray]

http://www.thunderpower-batteries.com/html/batteries.html
I run the TP8000-2S4P pack.

 

[4XADICT]

The Li-Po batteries will work with a standard ESC , correct? The guy at the LHS told me I couln`t run them with my Super Rooster(something about dischartge rates) but I don`t see why not. Of coarse he also said I wouldn` get much run time out of a 5700mha set up either. I realy want to run Li-po`s but still need to find a little more info.
Simtechray, how much run time are you getting and what motor set up are you running ?

 

[Ace]

I too have wondered about li-po's in crawlers. I have a 2100 li-po that I fly in a slow stick. My understanding about li-po's is you can't discharge more than 2C for extended periods meaning in a 2100 you can't draw more than 2.1*2 or 4.2 amps continuous.

They are improving the li-pos quickly and the discharge rate will go up.

With a two motor crawler, I discharge a 2400 ma battery in about 15 minutes so I must be drawing 4x2.4 or about 9.6 amps on average, so if you used a 8100 li-po they would probably support the discharge. Run times would be awsome!

As for using a rooster on a li-po, most plane esc's have a cut-off feature for low voltage. If you run a li-po down below a certian voltage, you permanently damage the battery. The hobbyshop may think you need a cuttoff esc to prevent this. Just don't run the li-po down to far and you should be fine.

 

[simtechray]

I use a single 600 sized motor and a super rooster. I have also used two magnetic mayhems with this battery, never had a problem. The website I posted has discharge rate info at the top of the page. Don't know runtime, I've never used it long enough at one time to discharge it. They hold voltage much better then a nimh so I'll play a 1/2 hour, then put truck away for a few days or weeks take it out and play some more. Hmmm, thinking about it, I probably recharge my transmitter batteries more then the li-po 8)

 

[Ace]

Simtechray,

I just saw your 8100's have a 5C rate, that means you could draw 40 amps continious. Awsome, thanks for the website.

 

[draganflyer]

I fly rc helis as well, lipos provide mine with the "go" juice. Yes, you have to be more careful with them, but believe me, you cannot jump a truck from any height and hit as hard as I can (and have) crash my helis. I have never had a lipo go into a thermal event from a crash yet, and a lot of heli and plank flyers are using them without problems. I've heard of these events, but I've never ever seen one.

Fliers use them for pretty simple reasons; much lighter weight, lots more run time, you can charge them one day and not use them for a month, and they still have the same juice they had fresh off the charger. The biggest drawback is the cost. You can get 3 dozen of those cheap shark packs for the price of one decent high amp lipo.

 

[RockyD]

Everyone interested in Li Poly batteries.

I just contacted Thunder Power Batteries and they recommended a new battery for my TXT-1. The TP7600-2S4P rated at 7.4V and 8C-10C continuous discharge rate. They are a 4" X 2" log that should fit my TXT-1 just fine and provide prodigious run times without taxing the battery. They are available at http://www.tppacks.com for $159.95.

They also recommended the following chargers for their batteries:
(NOTE - do NOT use the Super Brain 969 or any other chargers not listed below): Their caution.

Great Planes Triton
Astro Flight 109D
Schulze 6-330D
Schulze 6-636D
Orbit v6.3 software
Orbit Pro v6.3 software

Tower Hobbies carries the Great Planes ElectriFly Triton DC Comp Peak Charger for $129.99 and it requires a 12V power supply @ $89.99 to run it on AC. A good accessory would be the Great Planes Electrify Triton Thermal Probe for $8.49 to assure battery temps are safe.

If anyone has recommendations please let me know as this is my first R/C project and I am learning as I go.