550 TWIN BATT CHARGING METHOD

[DIRTBIKERICK]

Hi all, This is my first post, i Joined this morning, Great site, tons of info for my newbie self. I have a blade 400, just starting to hover, learning to crash and repair. I like the 550 hurricane, have one coming. My question is will i need two chargers for recharge in the twin batt setup or one, Do i charge both batterys at the same time in series?, I Know this might be a dumb question but it seems like ill need two chargers for two batterys right?, i have a cellpro 4s right now, great charger, Should i toss the twin batt setup and just get 1:confused: 6c batt, thanks, Rick

[lightbulbjim]

Well you can always just charge one at a time.

You can charge in series if your charger supports the number of cells (6S in this case). You'd need to obtain/construct the relevent adapters for both the discharge leads and the balance leads. It's also a good idea to check each pack individually and make sure they're the same voltage before starting the charge.

That said it's just as easy to get a second charger, and once you have have a couple of helis and multiple batteries it's useful to have more than one charger anyway. I currently have a BC6, and I'm looking at getting a BC8 to go with it sometime in the near future.

[Mikej]

Your C4S will work fine - it's what I use for the batteries on mine

[istandalone]

i just ordered the bantam bc-6, great value for the $. integrated balancer and discharger. you can do up to 6 cells, and if you have two identical (in specs, doubt brand matters) 3 cell packs you can use an adaptor to charge it as a 6s1p. there is also a couple other dual output chargers on the market. i also own the mrc 977, which i've had nothing but good luck with although there are plenty of people that have had problems with theirs. the only drawback to the 977 is it'll only charge up to 3 cell lipo, but for $100 worth every penny imho.

[DIRTBIKERICK]

Thanks for the info, i guess ill buy one more c4s, My new 550 should come in next week, looking forward to assy, It seems the two batt setup is more popular than one for this bird, ill get two tp3300 exv2 batts, better over amped then under right?, Im completly hooked on this heli stuff, flew fixed wing for years but this is a whole nuther ball game, Thanks again, Rick:thumbup:

[Zoobie]

I have a hyperion eos5i and a polycharge 4, which I have added a astro blinky balancer to. If I by mor Astro blinkies I could charge 5 packs at once. Usually before I go to the field I just put all my packs on at on time to top them up - I have 7 packs at the moment.

BTW the guys from readyheli did not think that it was a good idea to charge your packs in series? The interesting thing though is if I put both chargers on at exactly the same time they both end at the same time with the same no. of mah. I have marked my packs so that I always fly the same 2 packs together so that the cells stay sort of matched, something like a 6s 1P pack would.

[red_z06]

Thanks for the info, i guess ill buy one more c4s, My new 550 should come in next week, looking forward to assy, It seems the two batt setup is more popular than one for this bird, ill get two tp3300 exv2 batts, better over amped then under right?, Im completly hooked on this heli stuff, flew fixed wing for years but this is a whole nuther ball game, Thanks again, Rick:thumbup:

Two batt setup is not by choice but due to the original design intent. This is so the 450 sized heli packs can be used. Unfortunately, this is a bit of hinderance for the experienced pilots.

When using two pack configuration, be sure to label them as set A, B and such so the packs within the set will see exact number of cycles to stay in similar condition.

You can use 1 TP 1010C chager with 1 210V balancer to charge and balance the pair of 3300s in series and keep them balanced across the two packs for best performance.

[ukgroucho]

or a Hyperion 1210i with two balancers networked. Can charge and balance two packs (each up to 6S - so total 12S) and every cell is balanced across both packs. Also does A123s

I think Hyperion are coming out with a 0610 Duo - two built in balancers for up to 6S (2x3S) but it's not quite available yet and the pricing looks crazy; you can (in the UK) get a 1210i and two external balancers for the same price.

[vicrc]

I think the Celpro 10s is the best solution - internal balancer, 10 Amp output, 1c 2c 3c charge.

I have the 1210i also but man what a spaghetti factory when you got 4packs of 3s packs charging.

[Happy|Harry]

you could always charge them in parallel ;) as in 3S2P :)

phil

[mjr_larkin]

beginner question: What does a balancer do and is it optional for Li-Poly charges?

[Graeme67]

Hi Dirtbikerick,

I Charge 2 Kong Power 3S1P 3200 mah batteries in series from a Bantam BC8 charger and I'm having great results - I would highly recommend it. I have written a detailed thread of my experiences so far with my hurricane and posted heaps of photos of my battery setup & charging rig here: http://www.archeli.com.au/cobra/showthread.php?t=114656

You might find it helpful as there is some warnings as to what to look out for when charging and balancing in series.

Cheers
Graeme

[ukgroucho]

A balancer tries to ensure that all cells in a pack are at the same voltage. You can balance 'offline' or whilst charging.

The problem that these address is that all cells are not created equal - some perform better or worse than others. Also, depending on how 'well' the pack is assembled, there may be some differences in resistance for some of the solder connectors etc. so some cells may deliver a little 'more' or see different levels of stress during use.

What this leads to is that cells may end up at different voltages after the pack has been used. When you charge the pack the charger looks at the voltage across all cells. So for a 3S pack the charger will be aiming to get the pack to 12.63V total (4.21V per cell) or thereabouts.

Now, if your cells were unbalanced after use then you could end up in a situation where once cell reaches 4.21V but the other two are still at 4.1V. The charger is still not seeing 12.63V across all cells so it continues to charge - whilst the two cells that were at 4.1V are fine (still happily charging), the one that was at max V (4.21V) is now being OVER charged. Best case you just damage that cell and shorten it's life (significantly). Worst case you can cause the pack to puff or catch fire - the 'fire' situation is pretty extreme but it can happen if a pack is grossly out of balance.

If you balance whilst charging then you avoid this because the balancer is equalising the V across the cells - you will end up with all cells at max Volts at the end of the charge. Longer pack life (more cycles) and safer charging.

Some people claim that this is not necessary for packs with smaller numbers of cells (2S, 3S) but I disagree. For the small additional cost, balancing will pay for itself in terms of more cycles of packs and piece of mind.

My own experience is that as packs get older (more use) they are more likely to get a little out of balance during use - particularly if they are worked hard. I ALWAYS balance charge - everything; from 2S to 10S

[Graeme67]

beginner question: What does a balancer do and is it optional for Li-Poly charges?

A balancer is essential for maintaining Lipo batteries and should be used often. I use the Bantam BC8 charger/balancer and balance charge my batteries every time.

The balancer ensures the voltage is the same ( within .01-.02volt) across all the individual cells that make up you battery. If the individual cell voltages are allowed to vary greatly you will end up over working & over discharging some cells and dramatically shortening the life of the battery.

Hope this helps.

Graeme

[mjr_larkin]

thanks for the replies, i can now see the unwanted situations balanced charging is meant to prevent. now to select a charger :YeaBaby: