** LIPO BASICS ** Read me first!

[thegeek]

Please excuse the newb question, but when I see a batt like the turnigy described below (I'm just moving into bigger batteries at this stage) and it has two sets wires connectors - one charge - one discharge, is it mandatory that they be used that way (eg: could i discharge/fly using the Charge plug?

Spec.
Minimum Capacity: 1300mAh
Configuration: 3S1P / 11.1v / 3Cell
Constant Discharge: 20C
Peak Discharge (10sec): 30C
Pack Weight: 115g
Pack Size: 81 x 36 x 21mm
Charge Plug: JST-XH
Discharge plug: XT60

Thanks in advance.

Jeremy

[JoeW]

The JST-HX 'charge' plug (also called balance plug) can't be used to fly with. It's a multi-pin (3 or more depending on how many cells your pack has) and is typically a smaller gauge wire than the 'Discharge' plug they list there which is only 2 wires.

The Discharge one would plug in to your ESC on the heli. It can handle more current than the ballance plug and is only a red/black (+V/-V)

Chargers must at least use the balance/charge plug to be able to read individual cell voltages, and in the case of bigger packs use that 'discharge' plug also (because it can handle more current).

That's the short version but hopefully answers your question.

[thegeek]

Thanks JoeW, makes more sense now explained. It was a need for a JST (not the XT) to connect to my heli that prompted my question. I need to do some work on plug types now, thanks for the heads up mate.

J

[Commander4]

I have an AMPED UP 2200 3S 20C 11.1v 3 cell LIPO battery that has only been used a few times and now will not take a full charge. I can only get it up to 10.6V total. I have been charging it with the cheapo charger that came with my Heli that's supposed to be a balance charger. How can I get it to take a full charge? The charger balance light just blinks constantly. I also have a Electrifly 2100 11.1V 3S 20C LIPO that has been used even less, and will only take about

[The WoodCrafter]

Commander,
Sounds like you need a real charger, one that you can see what is going on.
One with a display and buttons.
How do you know what voltage the battery is?

[Slyster]

You also want a cell spy. Here's a good one. It has a number of modes and will tell you each cells voltage

http://www.hobbyking.com/hobbyking/s...dProduct=15516

[Vinno]

Originally Posted by Slyster

Yeah... full... even for a few days.. and your packs just won't have the same punch again.

Didnt know lipo were so sensitive, i always try to charge lipos as soon i get home and have them ready for next day or few days if longer then a week, i recharge to get back to full. this is bad?

So its best to get into the habit of only charging what you going to use for the day then go out and use, then leave batteries flat until the day your about to fly?

[Slyster]

Not flat.. that's just as bad. But store charged.. 50%.

[kimmik]

Originally Posted by Slyster

Not flat.. that's just as bad. But store charged.. 50%.

Thats not true. Flat is not too bad. When op says flat, im sure theres still a good 5-10% charge remaining anyway. I would only bother with 50% charge for long term storage - refrigerated.

[DominicD]

I never storage charge unless I am leaving it sitting for a few weeks. From weekend to weekend I just leave them discharge (20-30% capacity remaining)

[Slyster]

That's good to know. Maybe I won't be quite so anal next season. I always store charge all my packs after flying and it's time consuming hooking up all 6 packs in parallel etc. Thanks Dom.

[DominicD]

The only thing I have found to really effect Lipo life is leaving them charged for any amount of time (field charging is best) and discharging too low constantly.

[vtcnc]

Originally Posted by FuntanaS

I would add that the damage from leaving a battery fully charged in cumulative. Every hour that it is left fully charged adds up. Leaving a battery fully charged for 6 hours a day for a year is equivalent to leaving it charged for 3 months straight.

Can a LiPo be recovered? How? Is it losing charge during storage? Not sure why this would be happening? Can someone explain this?

[Arkanor]

Originally Posted by Slyster

Yeah... full... even for a few days.. and your packs just won't have the same punch again.

I'm going to call bull on this one. You have to leave them full for much longer than that to notice.

Think of laptop batteries, absolute worst usage case is people leaving them in while they're on AC and fully charged (hot, fully charged lipos). Doing this constantly I typically see them lose half to 60% of their life in 18-24 months. That's a far cry from 48-72 hours.

Best case: 40% in the fridge.

[The WoodCrafter]

Originally Posted by Arkanor

I'm going to call bull on this one. You have to leave them full for much longer than that to notice.

Think of laptop batteries, absolute worst usage case is people leaving them in while they're on AC and fully charged (hot, fully charged lipos). Doing this constantly I typically see them lose half to 60% of their life in 18-24 months. That's a far cry from 48-72 hours.

Best case: 40% in the fridge.

Lap tops don't use LiPo batteries.
They use Li-ion batteries.
A little different chemistry.

[Slyster]

Originally Posted by Arkanor

I'm going to call bull on this one. You have to leave them full for much longer than that to notice.

Partially agree.

We all know storing them full is bad... but some of the best pilots I know tell me that they can tell if a lipo was stored over a day fully charged... if fact it's somewhere here on HF where they were discussing it but I'll never be able to find it. HFG (DominicD now) was one involved and could tell.

But I do doubt the average pilot (the majority of us) would notice.

[WillJames]

Originally Posted by Slyster

Partially agree.

We all know storing them full is bad... but some of the best pilots I know tell me that they can tell if a lipo was stored over a day fully charged... if fact it's somewhere here on HF where they were discussing it but I'll never be able to find it. HFG (DominicD now) was one involved and could tell.

But I do doubt the average pilot (the majority of us) would notice.

I believe it is in the thread you just posted to, this one.

[kimmik]

I suspect the so called deterioration after storing fully charged for one day, is actually loss of the surface charge. A battery fresh off the charger will perform immensely well for the first few percent of charge and may give the illusion of being a much better battery than it actually is.

[hidiver808]

I understand that you can charge lipo batts in series that have the same cell count. Can you charge different mAh? For instance: can you charge two 2600mAh 6s and two 3300mAh 6s at the same time? If so, would the amperage be set to 11.8 at 1C? 35.4 at 2C?

[Slyster]

Yes you can charge packs with different C ratings and different capacities... it's all good. You just can't charge packs with different cell counts... like a 3s with a 6s.

I charge my 6s5300mah packs with my 6s4000mah packs together all the time.

Just average the charging rate. Really you can just slap on 6 packs and run the charger at the 30A max all the time.. since pretty much all packs today can handle 2 or 3 c charge rates.