trdsupra88

iTrader: (25)

Why do you charge two batteries at once? Isnt it less stress on the charger to do one at a time? Does it even matter?

avrcguy

iTrader: (11)

Any charger rated for a 4S lipo can charge this way with no problems. Regardless of whether it's a single 4S pack or two 2S packs in series, the charger sees it all the same way. It's important to remember though that with this setup (series wiring) you are only doubling voltage not capacity. So you still want to charge at the same rate you would a single pack.

For example it you have two 5000mah packs in series you should still charge at 5 amp, but set your charger for 4S (or 14.8v).

Charging the packs separately is fine too but it will take you twice as long. Assuming you have identically matched packs (capacity and brand) you should be able to run and charge the two together without them getting out of balance.

Hope that all made sense.

TonysScrews

iTrader: (13)

The problem is with charging the two packs at the same time wired in series you can not balance charge them. Best bet is to get the Hyperion EOS 0606i Duo charger and you can balance charge both packs individually at the same time.

party_wagon

iTrader: (29)

You can build yourself a ballancing harness that actually will let you plug in your two packs & ballance them. I run a123 packs in my cars. Often times I will run them as a 2s 3p pack & charge them as a 6s pack.

glassdoctor

iTrader: (4)

avrcguy and I talked about this already, and we are actually planning to offer a balance adapter/harness like partywagon is talking about, which will allow a balancer or balance charger to see the two packs as a single 4s pack. Something purpose built for this application. But there are so many different taps and such that we have some work to do...

Otherwise, you can also charge them in parallel, which is inherently self-balancing. (keeps the packs the same....but would require a balancer on each pack to truly balance everything)

Normally though, you should not have to balance all the time anyway. Topping off a couple times on race day should not throw them out of wack. Of course, if you know you have a pack that needs constant balancing... then you gotta do it. But most packs don't have any such problems.

trdsupra88

iTrader: (25)

Cool, thanks guys, I am slowl working up my arsenal for EL8, I have the MM ESC with Novak fan attatched, I am now looking into batteries, charger, and motor, thanks for the advice on charging...

TonysScrews

iTrader: (13)

party_wagon, You're absolutely right about the possibility of making an adapter to be able to balance the two packs wired in series as a 4S. The thought of making that adapter hurts my head though.....HAHAHA The Hyperion Duo charger makes things easy But I can understand that most may not be able to afford or even want to spend the kind of money teh Duo charger costs. But if you're serious about racing, you probably have a lot of money invested and i think the Duo is well worth it.

glassdoctor, I hope you guys do make these adapters. It'll make it a lot easier for guys new to the class who use 2S packs. I'm actually a big fan of using the 2S packs. But I think you should balance charge the packs all the time (as long as time permits). It will improve the performance and life span of the packs as well as make them safer (especially if you run the Novak system as one pack is drawn on more than the other. Same goes to those who pull 2S voltage off a 3S to 6S pack to run the fan, receiver, etc).

Best regards,

trdsupra88

iTrader: (25)

http://www.hobbypeople.net/gallery/963152.asp

http://www.amainhobbies.com/product_...ducts_id/18361

Are these the chargers you guys are talking about? 130ish doesent seem too expensive.

party_wagon

iTrader: (29)

Building a device that will wire up two packs in series is easy. 1st build a harness to wire up the two deans plugs in series. run a + wire to a deans side, then run a wire from the neg side of that plug to the + side of another deans & then run another wire from the - of that plug to the charger. Then take two 2s ballancing reciever plugs & wire them up to a 4s plug that will go into the ballancer. Here are a bunch of diagrams on how to wire up the ballancing plugs.

http://images.google.com/images?ie=U...num=1&ct=title

You will need to color code the plugs so that you plug them into the right spots when you charge. I charge my a123 cells like this because it allows me to charge a 2s 3p pack in 15 minutes w/ my 989. If you wire them up in parallel then it would take like 45 minutes to charge them.

ta_man

iTrader: (168)

The DUO charger (not the one you linked to), which is two complete chargers in one, usually sells for around $269.

strodedawg

iTrader: (85)

where can i get it online? how much? when?

badassrevo

iTrader: (12)

Send Glassdoctor a PM, he has two early production models available now!

strodedawg

iTrader: (85)

thanks

DARKWAV

You guys really seem to "get it" you know what I mean!

I could use something like that right now for align style taps.

Cain

iTrader: (294)

i know when I asked a couple of companies about making this adapter, they were willing to say how it is made but wouldn't do it because of liability issues.