Balanced lead only charging?

[texasrob]

I used to race electric cars before moving over to airplanes, so i have a lot of experience with 2S lipo batteries and chargers. I ended up exclusively using the onyx 235 (I had 3 of them for the racetrack) ac/dc power included, great safety features and they dont break the bank. I sold them along with my rc cars when i got out of racing a couple of years ago. Anyway, I was going to pick one up for my growing 3S battery collection. These Super Cub stock chargers charge through the balance lead only, where as most quality chargers charge with the main discharge lead and only use the balance lead for balancing. I can understand this, but I have also noticed that the manual for these batteries say to ONLY charge through the balanced lead and to only use the main EC3 lead for connecting to the motor. Could this be right? Many of the good Lipo chargers with balancing don't charge through the balance lead, you have to connect the main leads. Does this mean they can't be used for these 3s batteries? I currently have 3 of the stock 1300 mah 3S supercub batteries and a 2200 mah 3S eflite battery. Both of these say to only charge through the balance lead and not to use the EC3 leads for charging, so I am confused. I assume many folks out there are using nicer chargers that require connecting to the main EC3 leads for charging, but you know what they say about assumptions.

[flydiver]

If you are talking the raft of 4-button 'clone' chargers out there they ALL charge through the main leads and balance via the balance tap. You HAVE to connect the main leads. You can charge them ONLY through the main leads if you don't care about balance.

One really good charger out there that does charge through the main leads only is the FMA Cellpro 4s. It's a top notch charger but only good for 2-4S lipo. But it could comfortably charge 'crap' lipos at 3C when everyone thought that rate would make them explode. They are fairly idiot-proof and a solid product. I have 2.

There are other Cellpro chargers available that are the best in class if you are serious about your charging. You'll pay but if you hanker after powerful, fast, accurate charging they are the ones to get.

The Cub stock charger is almost, but not quite, bottom of the pile. I have seen worse in some of those really cheap Chinese RTF planes.

[texasrob]

Well, what I am getting at is that the instructions for these super cub batteries say to only charge through the balance leads and to not charge using the main leads. The 2200 mah 30C eflite battery I recently bought says the same thing. Why are the instructions saying you can't charge using the main leads? This is how all the high quality chargers work. Charge with the main leads, balance with the balance leads. And chargers like the onyx 235 let you balance while you charge. If I go by the instructions for these batteries, I can't use a charger that uses the main EC3 leads for charging.

[texasrob]

The verbiage I am talking about appears in two places in the battery charging instructions for my stock batteries and the new eflite battery.

"Be sure you use the shorter lead with the white connector for all charging. This is the lead protected by the Charge Protection Circuitry. There are two sets of lead wires on this battery. The shortest one is always used exclusively for charging."

And

"E-flite Li-Po batteries have two separate leads. The shorter lead with the WHITE (JST) connector attached is for charging only. It is the only lead protected by Charge Protection Circuitry, helping prevent costly charging errors. It is very important to note that the circuit only protects during the charge process. The second longer lead is for discharging or the power source for your airplane"

[flydiver]

Oh, with the CUB charger! I thought you were looking at a new charger.
Because that's the ONLY option you have. It will NOT charge through the main leads. It will charge the eflite battery OK (probably-see note) through the balance port only, but it'll take a ...l o n g....time.
I think you understand that part.

Got that?
OK, NOW, look for a new charger.

You should have kept the Onyx. It IS one of the variations on 4-button chargers I referred to. There are a LOT with quite a bit of variation in quality. The really cheap ones are.....really cheap.

DO NOT BUY AN IMAX B6 OFF eBay! They are likely copies of clones and some are simply garbage. The REAL IMAX is OK but you have to know the difference.
www.skyrc.com/antifake/indexen.php

Note-sometimes the Cub charger seems to never finish balancing other brands of batteries. It's a function of the sub-power and sub-par balancing capability. Having to do everything through the balance leads is limiting and the Cub charger is sometime simply not up to the task.

[texasrob]

The instructions I am referring to are for the batteries, though, not for the cub charger, so it makes me think it is a limitation of the batteries, not of the charger.

So bottom line is, in your experience, you can safely charge the super cub batteries and other similar 3C batteries with chargers that use the main leads for charging? I was worried when i started looking at the instructions for these 3C batteries that maybe they only liked to be charged through the balance lead.

[ginginho]

Feb 15, 2013 10:24:59 GMT 1 texasrob said:

The instructions I am referring to are for the batteries, though, not for the cub charger, so it makes me think it is a limitation of the batteries, not of the charger.

So bottom line is, in your experience, you can safely charge the super cub batteries and other similar 3C batteries with chargers that use the main leads for charging? I was worried when i started looking at the instructions for these 3C batteries that maybe they only liked to be charged through the balance lead.

In short, yes you are fine charging through the main leads if your charger is capable. Unless you have a charger that only charges this way (as Fly mentioned earlier) then you should also connect the balance lead. This ensures that the charger knows the cell count, and the voltage within each cell and therefore only provides what is required by the pack (and each cell) safely.

[hounddog]

Ears pricked up with this thread. I am currently using the cub charger to charge my skyraider batteries via the balance JST plug which it does just fine, although with 3S 2200s it does take a bit of time.

Waiting for HK UK warehouse to get some genuine Imax B6AC chargers back in stock and looking to buy one of those in preference to the stock cub lipo charger; I also have a 400 size toy heli with a 2S battery and balance tap charging only, will the Imax actually charge through the balance tap?

The charger that came with the heli lasted 2 charges and went kaput.


Cheers.

[flydiver]

Feb 15, 2013 17:39:48 GMT 1 hounddog said:

Imax actually charge through the balance tap?

Cheers.

No, only balance.
Charging is via the main lead.

Get an Accucell-6 or 8 or even better an iCharger.
The IMAX has had a LOT of problems and the 'fake' IMAX is garbage.

[flydiver]

Feb 15, 2013 10:24:59 GMT 1 texasrob said:

I was worried when i started looking at the instructions for these 3C batteries that maybe they only liked to be charged through the balance lead.

Those appear to be fairly regular lipos to me. I looked them up. Remember eflite doesn't make them, they just 'sticker' them and add 2-3x to the price.

If they make a battery with that extra cost, plus charging hassle they would pretty much guarantee failure of that product.

Charge it as a normal lipo in a properly safe manner. Nothing special there.

Note - You do see that you have a 2200mA lipo, capable of 3C charging (6.6A possible), that you are essentially limited to something like 1/2C with the PZ charger.
If you want to actually USE that charging capability you will need a more powerful charger than the raft of 50W limited 4-button chargers out there like your Onyx. Those are pretty much maxed out at 2200mA and 4S. A lot of people end up being surprised by this limitation thinking they are buying a hot shot charger that does everything for a cheap price.