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LiPo, the big guide thread *updated March '10* *


Garry

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hay guys not had a lipo for a while so just wanted to check im charging it right!! i have a 2200mah 45c 2s zippy so i would set the amp setting on the charger to a max of 2,2a to charge these??

cheers

Damon

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yeah thats right damon :thumbsup:

cheers mate also something i noticed the charger says end voltage 2s 8.4v i thought 2s was 7.4v or am i being stupid lol??

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  • 3 weeks later...

Sorry to of ask this if it has already been awsnerd. I have 4 sets of 2s batterys on the way. For the first charge and or, first few charges is it safe to charge them as normal or use a less amp range for charging. The battries are 2s c45-?? (cant remember now) with 5000mha compacity. Also using them in the car, can I use them normaly or will I have to "break them in" for a few cycles and take it easy?

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  • 3 weeks later...
  • 4 weeks later...

how do you charge a lipo for storage ??? i have Fusion Ethos LX41B pro charger and no mention of storage charging

That charger doesn't have a storage mode- you'd have to manually stop the charge once ~50% capacity has been pumped back in ( ~3.8v per cell ).

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As a newbie to rc have a maverick vader and I am using 3200mah 3s lipos and I only seem get about 20 mins of run time, is it better to get something 3s with a higher mah or 2s with a higher mah not sure which would be better, as in the manual it talks about running it on lipos but not which ones, I just got the ones that were recommended by the store. Any hints or tips would be gratefully received thanks

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As a newbie to rc have a maverick vader and I am using 3200mah 3s lipos and I only seem get about 20 mins of run time, is it better to get something 3s with a higher mah or 2s with a higher mah not sure which would be better, as in the manual it talks about running it on lipos but not which ones, I just got the ones that were recommended by the store. Any hints or tips would be gratefully received thanks

Voltage determines speed ( 2s = 7.4v, 3s = 11.1v ( nominal ) ), mah capacity determines runtime. If you are happy with the speed and the temps are good ( keep motor and esc below 180

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  • 2 weeks later...

Can someone help clear this up for me please....so if my esc has a rating of 120A, and I have 2x2s lipos running on it which are rated to 5800mah 45c = 261, is this number multiplied by two, or does it remain as 261?

So if my other esc had a rating of 150A and I wanted to run a 6s lipo, would this mean that I'd need a lipo that had a minimum of 150A rating, like a single 6s 5000mah 30c, but if I got 2 x 3s which were 4000mah 25c, these would or wouldnt work? each would be 100A, does that mean it totals to 200A or not? This has me confused....hope this makes sense

Thanks in advance.

Mo.

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the esc only takes what it needs the rating is what it can handle so you dont have to have the amount it states

This actually confuses me more :shockingscary: I thought the lipos you choose have to meet the esc rating of X amount of amps as a minimum. The guide at the start of this threads mentions

''C-ratings aren't the only thing to look at when buying a pack though. Some people will say ''A 30C pack is all you need''. This statement is very misleading and potentially dangerous. For example, say you have a car with a brushless system which is rated at 120A. That means, you need a pack which will supply 120A when asked. So, you should try a look for a pack which exceeds this requirement. This can be done with a combo of higher capacity/lower C-rating, or lower capacity/higher C-rating. However, don't automatically think that a high-C-rated pack wil always be enough. For example...

If someone said you'd need a 30C pack to power the 120A system, it may sound like any 30C pack would do. Is a 1500mMAh is OK because its 30C? It definitely isn't OK.''

Am I reading this wrong?

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Ok, thanks for clearing that up Jack :thumbsup: .....I was just confused, as I run a savage flux hp, and on their website it says to run a minimum of 4000mah 25c lipos, which I thought doesn't meet the esc requirment of 120a, only 100a. But you've cleared that up now lol. So if I bought two 3s 3300mah 65s, this would be ok?

Edited by Mo.
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Ok, thanks for clearing that up Jack :thumbsup: .....I was just confused, as I run a savage flux hp, and on their website it says to run a minimum of 4000mah 25c lipos, which I thought doesn't meet the esc requirment of 120a, only 100a. But you've cleared that up now lol. So if I bought two 3s 3300mah 65s, this would be ok?

Not for a savage flux really- capacity matters as much as C rating. True, the total current output may be the same if you vary capacity and C rating, but you will drain low capacity packs too quickly which may still damage them ( a thirsty model needs a big fuel tank, a good analogy to compare it to ). It takes a while to get ones head around some of these issues, knowing what spec batteries would be suitable for any given motor, esc and type of model, but you'll get the hang of it ( read my tutorials page ;) ).

As for C ratings on lipos, when they are wired in series ( 2x 3s = 6s for example ) the C rating and capacity remains the same, only the voltage increases. When you wire batts in parallel, then the voltage and C rating stays the same, but the capacity increases.

The advice in the HPI manual is very odd and incorrect though, it was noted a few years back but they never updated it for some reason which is rather poor.

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  • 3 weeks later...

How long would you leave a battery in its charged state rather than storage state?

When I set my charger to storage mode it only goes up to 1A, much lower than when its set to charge or balance. Is this normal?

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Just thought I'd link this thread as a reminder about the risk.

The chap who's heli this is is a very good friend of mine and has many years experience using lipos.

http://www.rcheliaddict.co.uk/main-discussions/85641-bad-day.html

Due to centre of gravity issues in the heli the batts had to be fixed at the rear of the fuze and couldn't be removed for charging.

Investigations are still on going.

Keep safe

Joe

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it can happen to anyone thay can be like a time bomb waiting go off i was flying my t-rex 600 last year wen my 6s pack blow i was lucky tho as i dident use the esc,s bec and manged to land it just lol

after that i never fly or drive with a pack that has any dents or in anyway puffed up

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