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Lipo charging


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Hi
I have always balanced charged my lipos by using balance plug and output lead, no prob
However I have just purchaced a lead from Century which enables me to charge up two 3 cell lipos at the same time by telling the charger that it is a 6 cell lipo. My question is what do I do with the two main leads from the lipos. I know the balance leads are both conected , is that enough
Garry
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Unless your charger can charge through the balance lead you will need to connect the 3 cells lipos in series to make it a 6s, i.e. connect the +ve on one to -ve on the other and then remaining two terminals to your charger.
 
If they are fairly large batteries it might not be much quicker as the max watts of the charger might be the limiting factor.
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If the lead is configured to show the two packs as series wired ( 6s ) then you will need to connect the two packs main leads in series also. Personally I dont like series charging packs, and much prefer to parallel the packs up ( balance leads also ) which then equalises all the cells and keeps them like that during charging.
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Does your charger have a six cell balance socket? does your new lead fit it if it does? You should be ok provided the answer is yes to both questions. You will get a slower speed charge than you get using the power leads/balance lead method.
 
If it works as if it is a Y lead then you will not have your charger doing the normal monitoring of the cells. In which case I would be wary.
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Thanks for the replies lads. Yes the charger does have the facility to charge through the balance leads and it does have a 6 cell balance socket, should have told you that in the first place, sorry.
Timbo, not sure I fully understand what you mean about paralell and series charging, can you elaberate in simple words and if poss a diagram
Garry
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Simple. Just the same way as packs are configured for use in a model, they can also be configured for charging.
My old article on batteries explains parallel and series wiring, HERE.
A relevant extract.....
"Another of the great things about them is that we can happily join identical cells together in either series or parallel, or indeed a combination of the two, whereas this practice is not recommended for the older type of nickel based cells.
This combining of cells in various configurations is where the pack designations come into play. If a 4-cell 2100mAh Li-Po battery is connected in Parallel to another identical battery this results in 4 cells in Series, and 2 batteries in Parallel, or, in other words 4S 2P. The nominal voltage remains the same as one battery, which in this case (4 cells @ 3.7V each) would be 14.8V. However the capacity is doubled and this newly formed 4s 2p battery now  boasts 4200 mAh capacity. To increase the volts, we join in Series, to increase the capacity, we join in Parallel. Combining both increases both."
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The series adapters I've seen in the past which allow you to connect 2 x 3S batteries via their balance ports have a main output which is the sum of all 6 cells.  Therefore the method of using them is as follows:
 
- Connect the two batteries to the adapter via their balance ports;
- Connect the main out of the charger to the main out of the adapter;
- Connect the 6S balance connector from the adapter to the charger;
- Commence balance charging.
 
In other words, no need to connect the main outputs from the batteries to anything.  Mind you, this holds true only for the adapter that I've used before, it doesn't necessarily apply to the item you have Garry.   I tried googling for Century balance adapter but can't find it.  Why not post a link or a photo of what you have any we could advise you better?
 
Ps.. I'm with Timbo - parallel charging is generally much more useful once you get your head around it, but perhaps best left alone if you're not confident about how to connect things together.

Edited By peevie on 21/12/2009 08:14:39

Edited By peevie on 21/12/2009 08:15:57

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Timbo Its the £4.99 lead I have bought not an actual charger. My two chargers are
Fusion Elysium LX 60B Pro and  an H 1300 power charger 5 Hope this helps
Will either of these chargers charge through the balance leads. Thank goodness you two know what you are talking about
Garry

Edited By Garry Pollard on 21/12/2009 17:07:30

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Im sorry, but I must be thick or summat ( dont answer that ! ) but what then is the large power lead and fitted deans connector for?
I assume this connects to the chargers main power lead input, where the battery would normally go? If so, then the batteries are effectively being connected to the chargers main output, and the batteries are fed this main power output via the two extreme end connections of the balance socket. It can be seen from the picture that these two main leads are simply conneced to these charger wires within the heatshrink covering.
What I dont understand, is how the flimsy balance wiring is carrying the main - potentially high - current needed to charge at the usual 1C.  I made up and use frequently use a "parallel" connector adaptor board for charging several packs together, but never exceed 1.5A maximum as this current has to pass down the thin balance leads, which are only designed to carry small trickle "bleed" cyurrents used for balancing cells.
I also made up my own special harness ( shown below ) which I use to charge 2s receiver packs in my models via the 3 pin balance plug - but again, never higher than 1 - 1.5A maximum.
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Tim, that's exactly how it works and why I described the connection sequence as including connecting the balance leads and the main out of the charger to the main output connector of the adapter.  The main leads of the batteries themselves remain unconnected and you're correct, this is only suitable for moderate currents (I'd suggest no more than 1.5A).
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And this is my home made parallel charge board.
If only using smallish charge currents ( max 1.5A ) then no need to connect all the main battery leads together, simply connect one of them to the charger output, and plug the balance plug only of all the others into this board. This then effectively connects all the relevant cells in parallel, and charges through the outermost balance plug connectors ( which are effectively connected internally to each battery main positive and negative lead )

 
Here , three packs are being balance charged together, but only one has its main leads connected to the charger output.

 
Here is what the charger "sees" - just one 3s pack, albeit 3 x times the capacity of each pack.
Of course, this method can only be used with same cell count packs, but their capacities can be different - all packs should also be in a similar state of charge /dischrge  before plugging in the balancer plugs.
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Thanks for the time and trouble you are both going to for me. I am saving  the replys from both of you as I think I need to study them in great detail. The lead is on its way and I hope there is an instruction sheet with it. The reason I went for it was that the lipos I was going to use power the mini pulse and I tend to take two to the flight line and have two flights without going back to the pits (quite a walk). I use a genny to recharge the lipos and thought how good it would be to be able to recharge two off one charger. Maybe there is a flaw in this. I have 4 3s 2250 lipos for this model
Garry
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The flaw is that you can only charge slowly ( around 1.5A ,maximum )
On your 2250 lipos this means re-charge times of almost 2 hours
Incidentally, even without the adaptor, and connecting the packs in series "normally" to charge in the normal1 hour,  your charger needs to be able to pumpout 60 watts.
Can your charger do this ?
Mmany chargers ( even so called "better" ones)  are limited to 50 watts.
 
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Felt I had found the flaw, now you have confirmed it. My own fault, should have asked first. The pro charger will only put out 50 watts The other one is no good as it is limited to 5 cell lipos not 6
Ah well I suppose I will find a use for it when it comes, and if anyone has any ideas dont forget the moderaters are watching.
Thank goodness it was only £4.99 not £499. I will seek guidence in future I promiss and one day I will learn to spell. Thanks for your time, and Timbo if you can tell me what to use it for feel free, as I dont know if you can moderate yourself LOL
Garry
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