Cammy1230

Hi Guys

Just got a question. I am familiar with charging and using LiPo's, but I have always stuck to the spec sheet when it comes to charge rates. My question is can high quality packs like VENOM be charged above 1C, come on turnigies can be charged at 5C? Do they just say 1C to cover their asses and protect the consumers that have never own/used/charged a LiPo before?

Any input greatly appreciated.

Grasschopper

iTrader: (54)

I'm interested too. SMC LiPos come with a sheet and on that is charging instructions which say that you should (can?) charge at 2C and that you shouldn't charge BELOW 1C. There was a post in the SMC thread where a user for a 7200mah battery said he regularly charges at 1A and when at the track bumps it up to 6A both of which are under a 1C charge rate.

So to add to your question above, how does charging at below 1C affect the performance/longevity of the pack?

I know back in the NiCad days the cells got "trained" on how to discharge by how you charged and discharged them. Use a slow charge rate and they would discharge slowly. Don't discharge them fully and they would eventually only perform well down to that level. But it was my understanding that these were out the window with LiPo.

Cammy1230

+1 Good question.

Mullet1

iTrader: (16)

the SMC packs state on them they can charge up to 6c. I charge my 2s 7200's and 4s 6500's ones at 20a. they work fine.

Wildcat1971

iTrader: (84)

most of the packs today are rated at 2c. And the "good" ones are 4-5c

asc6000

iTrader: (15)

read this thread , interesting stuff
http://www.rctech.net/forum/electric...-more-now.html
your guess on why they state 1c is probably correct when all is said and done.

Cammy1230

I charge my Turnigies at 20amps, they didn't have an issue. I would say I can now up the amps on my charge rate for my VENOM's, a hour gives me the right shit's lol.

Wildcat1971

iTrader: (84)

I walk away from my charger a lot when racing and stuff, plus I race with an 8 year old, so I try to keep it reasonable and fast. I have a 10amp charger and a 20 amp charger. But imo, 2x 10amp chargers for 2s racing is plenty. so 2c is fine, not need for more. but if time is short I will go 3c.

Cammy1230

Just read this one that thread, good info.

"The ONLY thing that charging at higher amps will do is: Charge the battery faster, cut down on the life of the pack (from 300 cycles to 200 cycles maybe all speculation), and it will warm the pack internally which will decrease IR and increase voltage. But with all the big races checking battery temp it will not help as it wont pass tech.

The heat is the only reason it increases the voltage and lowers IR. If you let the pack cool to room temp and check it it will be the same as if you charged it at 5 amps. I have yet to see a charger that has any special voodoo built in that will charge and make a battery faster without using heat.

Ive been charging at 40 amps since December with the ICharger Duo 4010 came out. I raced every week all the way up till the birds. I only keep two packs to my name at a time. I practice and race on those two packs every week in TC. Those packs are still good today as they were new in December. The 40 amps thus far has not shown any ill effects at all. Generally when I go to the track its 4-5 charges per pack per day. There were some 3 day races in there too.

The pack I won the birds with was charged at 40 amps every single charge. I used it in both 17.5 and 13.5 TC all week in every practice and every race. Then I sent it to Josh Cyrul and he did the same with it in Modified and 13.5 sedan which he won both classes. That battery was put through hell and still cycles the same as it did when it was new a week before the birds.

The key to keeping batteries fresh is USING THEM! And making sure they dont sit with a full charge or zero charge in them. Not being used is a Lipo's worst enemy I have found."

Cammy1230

Is it better to have a low or high IR?

Wildcat1971

iTrader: (84)

low IR

Cammy1230

Ha ok cheers. Someone on that last thread was answering some questions and said

"Q:What amp rate have you been charging the same pack previously?
6 amps - Now 20 amps - went from 47.3 IR to 6.1 IR on the first charge!"

Wildcat1971

iTrader: (84)

he was claiming that high amp charging brought a pack back to life. if you read it on the internet its true

Cammy1230

Sarcasm?