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Boy racer
29-09-2009, 09:01 PM
I want to start useing lipo cells for off road at Batley:), my problem is i know vertualy nothing about them:confused:. How many packs do i need, how long to charge, run times.. ect, any help please? Also there seems to be a lack of choice in saddle packs, which are the best to go for??

JCJC
29-09-2009, 10:37 PM
If the lipos need to be BRCA approved then there is the list,
http://www.brca.org/BRCA/elecboard/news/2009%20BRCA%202S%20LiPo%20List%20.pdf

for saddles first make sure they will fit in your car, we use the vampire cells in both a D4 and an X6 (also takes a stick pack), love em.

You need a dedicated lipo charger, do not charge with/as nimh they will burst, set the charger amps, press charge and let the charger tell you when they are finished, race. charge, race again etc.
We balance charge approx once a month, this evens out the cell voltage, and do not fully discharge lipo's, if the car feels as if its dumping or voltage drops below just above 6volts stop and recharge, do not leave in the car connected. For extra safety charge in a fireproof bag, lipo sac.

We find we can manage with one set, but two is nice.

Oscar
30-09-2009, 08:35 AM
I want to start useing lipo cells for off road at Batley:), my problem is i know vertualy nothing about them:confused:. How many packs do i need, how long to charge, run times.. ect, any help please? Also there seems to be a lack of choice in saddle packs, which are the best to go for??

The best way is to speak to someone at the club, meeting dates are on our website (currently weekly until further notice).
There are very many reputable brands out there, Demon and Trakpower are my recommendations, but thats just personal choice;)
If you are running club days, I would suggest buying 2 packs because with the short in between rounds you will not charge up in time on one pack.
Charge time depends on how large the batery is, and how much you have used out of it, but from flat it will take over an hour.
Run time again depends on how large is your battery, and what type of car & motor you use.
hope that helps:thumbsup:

Oscar
30-09-2009, 02:37 PM
Someone has just sent me this by PM (thanks you know who you are), and it seems like sensible advice which you may find useful:)

There is alot of misinformation out there but I did much research before I dived in.
There are basically 4 things that matter on a lipo, the capacity (in mAh), the 'c' rating, the size (if it fits your car) , and of course price. Unlike other types of battery, the capacity in mAH (typically between 3300 and 5000), as well as indicating run time also relates to the amount of current it can deliver. The way it works is 'c' rating, for example 35C, then multiplied by the capacity/1000, so a 5000 mAh 35C can deliver a current of 35 x 5000/1000 = 175A, while a 3600 25C can deliver 25 x 3.6 = 90A. I have various packs and find for 2wd even the lower rated ones are fine whilst for hot motors and 4wd you are better off with something at the upper level example. Run time never an issue but power delivery can be.

Store Lipos part charged, so I usually run the race and then just put them away, so they would be around 50% charged.

As far as brands don't worry about 'designer' brands as they all come from a few factories in China originally. The Intellect ones you can buy on ebay shops from Hong Kong are much cheaper that the 'branded' ones in this country and are BRCA approved (check the list) and perform equally well. In fact they are actually the same batteries with a different sticker on and marked up, have a look at the Demon ones or the Epic ones, they are re-stickered intellect batteries. You are talking the difference between 45 quid and 80 per pack, and 2 packs is fine.

Buy a balance charger for around 30 quid.

Boy racer
30-09-2009, 09:51 PM
Thank you :thumbsup: lots of help, i think i'll go for the Trackpower's, i like the gold case's, lol :p