Best budget charging for 4S LiPo?

[LI-ghtcycle]

Hello, I am looking to see what would be a very cost effective, safe and user friendly charger & power supply to charge six 4S Turnigy Nano Tech packs, they are 6AH, and have a 5C rated charge rate, however, something with just 2A charge rate would be just fine, even individual chargers/power supplies for each battery would be fine, just don't want bottom of the barrel stuff, just the best easy charging decent stuff. It would be fine if it took 4 - 6 hrs to charge them all up, but would prefer that they could all be charged at once.

Thanks!

 

[neptronix]

I would look at some 8s chargers... which you can balance two packs on if need be.

I like iChargers because they have a lot of options, but check the reviews on HK. the 2xxx and 3xxx models seem to be problematic.

If you are charging many packs at once, you may want to get a weaker 8s charger to start, then save up your $ in order to do a meanwell setup to quickly bulk charge all your packs quickly in one fell swoop. I hear those nano-tech batteries charge like A123's, so if you had a meanwell that could dump out many amps, you could be looking at a 1 hour charge or less for the whole shebang O_O

 

[dogman dan]

People seem to say otherwise, but my turnigy 150 watt 8s chargers seem fine to me. With up to 7 amps of power, you could charge 4 paralelled lipos at once at nearly two amps each. Well within your time frame. Nice price.

Just rig a paralell harness for em, and charge em all at once. Once in a while, check for inbalance. You only need to balance charge when actually out of balance significantly. Ignore all that stuff from guys sweating it when a battery is out of balance by 0.01v. Maybe fuss if it's out by 0.1 . You could easily find yourself only balancing every 50 cycles if you aren't hammering the cells to 100% dod.

Power supply I can't comment on. I still use an old 12v sla charger and a lead battery for mine.

 

[LI-ghtcycle]

Good Stuff! Thanks guys, I am looking at this to see what would be the best deal for a buddy of mine that might join into the LiPo game using my 4S batteries to power a DD 9 x 7, so I am not as concerned about speed of charge as simple and safe with reasonable price tag.

How would one go about balancing with a 8S charger for 4S packs?

 

[neptronix]

Just rig a paralell harness for em, and charge em all at once. Once in a while, check for inbalance. You only need to balance charge when actually out of balance significantly. Ignore all that stuff from guys sweating it when a battery is out of balance by 0.01v. Maybe fuss if it's out by 0.1 . You could easily find yourself only balancing every 50 cycles if you aren't hammering the cells to 100% dod.

Yup.. these batteries get super unbalanced at the bottom of their charge but the top is no big deal.
My suggestion to you is to get a charger than can set the top voltage though, here's why.

If you are bulk charging to 4.20v, occasionally a cell will go over by 0.01+ voltages. I set my charger to 4.17v per cell when bulk charging because it gives me a buffer of 0.03v per cell. I lose maybe 100mAh of the capacity of each pack? no big deal.

With a charger that i can't set the top voltage on, i'd be nervous about that. I don't think batteries would explode of charged 0.05v over, but it certainly doesn't help their lifespan.

Chargers that can do this are the hyperion and icharger line, as far as i know.

 

[LI-ghtcycle]

Yeah, I'd want to avoid "bulk charging" altogether, I have seen some people listing inexpensive HK chargers before, just thought I would check and see if anyone else had a suggestion.

He's too new to the game (and too risk intolerant) to do anything as "risky" as bulk charging LiPo. He might be best served to get the 36V LiPo pack from Amped Bikes as far as a simple plug in the wall and forget deal that has a BMS to keep things safe, but I suspect that he like the vast majority of us won't be happy with just 36V for long! :wink:

 

[neptronix]

Disconnecting each pack to charge is gonna get old quick, so i'd tell him just to get a ping pack or an american made one honestly. If you are a total electronics newbie, it will ultimately save you $ and maybe your home, lol..

Lipos are for the hobby market, definitely not for the mainstream.

But my bone simple 10s setup with 5s packs in serial + icharger 1010b+ is what i'd recommended if you have to use lipo.
with 12s, you want a charger that will do 12/14s and keep things in serial so you don't have to keep connecting/disconnecting things to balance charge. That gets old quick.

 

[dogman dan]

What's his budget? Will he ride daily? Your original question was how to charge cheap, not how to charge the most convenient. Since you mentioned multiple chargers, I assumed disconnecting was acceptable.

Step one might be to permanently series some of the packs into 8s packs instead of 4s. If you plan on using 12s, then get a more expensive charger and make up some 12s packs that charger can charge in one piece.

For a noob, running a 9c kit, It's hard to beat the advice to get a 48v 15 ah ping. But it will cost a bit. Still calcualtes out theoretically as one of the cheapest ways to go per expected mile of lifespan. Nice thing about a ping is you pretty much have to buy a battery with loooong range because of the c rate. Then you realize right away how nice that can be. BTW, the c rate is 2c, but I recomend sizing the battery to about 1.5c max. So a 15 ah can handle the 22 amp controller in a 9c kit fine. 10 ah size is pushing it for a 22 amp bike.

Hard to say what the max lifespan might be, but my oldest ping now has over 5000 miles on it. I stopped keeping track a year ago. It's almost 3 years old now, and paid for itself after about 6 months of daily riding. So by now, it's a really cheap ride! I'm pretty sure some others have even higher mileage. I figured on counting on 1000 10 mile cycles, or 10,000 miles of riding. 6 cents a mile at that expected lifespan.

 

[sangesf]

If they made 10s 10ah LiPo's cheap enough, that would help with the charging problems..
Do they even make such things?
(and yes, I'm a complete lipo newbie)

 

[neptronix]

If they made 10s 10ah LiPo's cheap enough, that would help with the charging problems..
Do they even make such things?
(and yes, I'm a complete lipo newbie)

They do make 5ah 10s packs in nano-tech, but they are really just two 5s packs connected together.
But the idea is that you get two 5s packs and use a 10s charger to charge them both as a serial strand.

So basically you make 2 10s 5ah packs and you got what you're looking for. You can charge each 10s pack separately if you are nervous. If that is not easy enough for a newbie, i dunno what is

 

[LI-ghtcycle]

Hmmm but what about balancing? Wouldn't he need to balance them individually?

 

[neptronix]

Hmmm but what about balancing? Wouldn't he need to balance them individually?

Unfortunately, yes. If you wanted to get a 100% accurate balance, you'd have to do each 10s pack separately.

 

[dogman dan]

Or just paralell them, and charge as one pack then disconnect and series connect to ride. By plugging in a paralell adapter to the balance wires, you can still balance multiple packs. Essentially, you create a large pack for the balance charging by paralelling both discharge wires and balance wires.

I still like the two chargers idea. That way when not if one craps on you, you still have one left to do your charging.

 

[neptronix]

paralleling is the way you'd want to do it ultimately, but for a newbie who doesn't know what they're doing and doesn't spend a lotta time on this forum.. and is kind of in the dark.. i dunno.

Here's the thing about zippy/turnigy batteries... the cells are not AH matched, they are internal resistance matched.
Sometimes a pack will have a weak cell or two in it, missing ~500ah!
Other times a pack will have a strong cell in it, having a few 100ah more!

It is a real crapshoot. I have 10 5s battery packs and they all act differently.

So if you parallel a pack and hand it to a newbie who doesn't have the hobbyist mindset, you better be handing them one that has gone through a few charge + discharge cycles to see how the far the cells get out of wack with 0-10% mah left.

You parallel a pack together that has a weak cell or two and you got a liability on your hands when that thing starts puffing and is ready to catch fire down the line because one cell is missing 1000maH and is getting fed up at this whole, being discharged into the 1-2 volt range thing.

 

[LI-ghtcycle]

What's his budget? Will he ride daily? Your original question was how to charge cheap, not how to charge the most convenient. Since you mentioned multiple chargers, I assumed disconnecting was acceptable.

Step one might be to permanently series some of the packs into 8s packs instead of 4s. If you plan on using 12s, then get a more expensive charger and make up some 12s packs that charger can charge in one piece.

For a noob, running a 9c kit, It's hard to beat the advice to get a 48v 15 ah ping. But it will cost a bit. Still calcualtes out theoretically as one of the cheapest ways to go per expected mile of lifespan. Nice thing about a ping is you pretty much have to buy a battery with loooong range because of the c rate. Then you realize right away how nice that can be. BTW, the c rate is 2c, but I recomend sizing the battery to about 1.5c max. So a 15 ah can handle the 22 amp controller in a 9c kit fine. 10 ah size is pushing it for a 22 amp bike.

Hard to say what the max lifespan might be, but my oldest ping now has over 5000 miles on it. I stopped keeping track a year ago. It's almost 3 years old now, and paid for itself after about 6 months of daily riding. So by now, it's a really cheap ride! I'm pretty sure some others have even higher mileage. I figured on counting on 1000 10 mile cycles, or 10,000 miles of riding. 6 cents a mile at that expected lifespan.

Honestly I don't know his budget exactly, but I think pretty much low as you would imagine, I'm just not wanting to steer him in the wrong direction with an ultra cheap and potentially dangerous LiPo charger.

I agree that a Ping is a great option too, and he might go that direction, however, if 36V fits the bill for him (and if anyone it could it would be him) then the Amped Bikes tube battery will most likely be his choice, he works for the LBS, and being an Amped Bikes dealer, I'm sure Al will give him a deal on the price.

The more I think about it, I really think that is the best option, I think Hobby LiPo might be too big a leap for him at this point. Thanks for all the info though guys!

 

[vanilla ice]

I've had good luck with the cheap HK chargers like dog. Better luck there than with their lipo.. had a few cells go bad but no charger problems. The eco-6 or 8 would work. For sure its a pain to disconnect your pack every time you charge though. Not the way to go if you are going to use the bike daily.

 

[LI-ghtcycle]

Yeah, for me that's not such a big deal, but hey, if I can get something to make my life easier for not much more than I already paid for my B6 Duo, and I can do 12s as a group inc. balancing, that is what I will do, but I think my friend would be better off just using something plug-n-play.

Becides, it gives me the excuse to buy more Nanotech since I won't be selling my packs to him!