They say 7.4 because they are sold as a 2S pack. The cells are made to be used as a single two piece battery.

Look here: http://www.smc-racing.net/index.php?...&product_id=69

They are sold as a 2S pack, Both marked as a 2S pack. Reading the description tells you they are 1S packs attached with a jumper wire.

The balance wire that goes to the jumper wire, between the two 1S bricks/saddles (along with the balance wires going to the main positive and main negative to make a standard 3 wire 2S balance connector) allows the charger to control the balance of each brick/saddle. (Picture in post #8)

Within each brick/saddle, the cells are connected in parallel, this parallel connection ensures balance between the individual cells within each brick.

Its pretty simple. If both halfs of the saddle have a separate balance port then it's 2 individual 2 cells. Which its not. Thats not how 2s saddles are produced. If each individual half of the saddle pack does not have a separate balance port then they are 2 individual 1s. Which is how 2s saddle packs are made.

OP I'd pay attention to Dave H. Just my .02

Ok I get it. Some may think I'm arguing for the sake of arguing, but that's not so. My concern was with two gel sacks of chemical in one battery, being able to monitor charge on both sacks, not battery packs, but the two sacks of gel inside.

Yes, when two battery packs are charged in series they balance, but you still have a single balance lead on each pack, combining on both to make 2S leads, which has 2 sacks of gel inside on each.

Just saying they charge because their saddle packs doesn't really answer the questions. Most people probably don't even think about stuff like this, because they are told to charge it a certain way and it just works, and that's fine with them. I guess I want to understand the process a little deeper than the average joe.

Youre clearly not understanding how current flow works between parallel and series connections.

Each of the cases/bricks in the saddle pack has 2 balance wires, there are 3 balance wires on a 2S balance connector. A wiring diagram is attached for reference.

Assuming a 2S2P saddle pack for the moment, the left case has 2 cells directly connected, with a balance wire to each end/polarity. Same for the right case. The middle balance wire is shared, and is part of the series jumper wire between the 2 cases that make up the saddle pack. The end balance wires are essentially connected the same as the main negative and positive large charge/discharge leads. Thus the charger can see the voltage of each case, across the respective pairs of balance wires, and control it.


Of subject a bit, but a significant portion of the standard 1/10 scale 2S packs are 2S2P and wired the same way, just all inside of one case.

I think he is asking what keeps the seperate cells wired in parallel in each block of cells in balance. Maybe?

Gentleman - Firstly let me apologise for not replying as I actually forgot I posted but finally worked out how to search threads I entered - I did actually sort it out
The cells were not properly balanced & therefor one cell was much lower than the other causing an error with the charger
Took it to local RC shop & they boosted the charge to recover cells to an appropriate level so that the charger recognized the battery
They are charged together as 1 battery with balanced lead - charged at 5.0A @ 7.4V (2s)
Have attached pictures to show so that it clears it all up
One pair was puffed so obviously not looked after
I appreciate all the advise & information

:blush:

:blush:

You Sir are absolutely correct / spot on !

Good to hear you've got it sorted, always like to know what happened with these trouble shooting threads.

I do think Spookie has a fair point about the labeling, not as clear as it could be. Not sure how to fix it though, labeling each saddle with 3.7V could be confusing too I suspect?

TBH I think the labelling is quite sufficient - you need to treat them as one battery hence the loom wiring with them
From initially reading some thread I thought I had to double things - now that would have caused a whole other issue.
While one pack is puffy have purchased a saddle pack from Hobbie King & put the others aside for now :flaming: they still work fine & hold their charge just a little concerned on them & charging
I do put always in LIPO charging bag just to be safe

AGAIN much appreciated advise in this area - hope I didn't put the thread in the wrong place

SO i just got a new saddle block battery. And well it has 2positve tube holes A balance one in the middle and 2negative tube holes on the right. How do i charge this?
i have a set of wires for a saddle with a +/- and a jumper with the balance attached. and i also have another set with +/- and a separate balance tube. so whats up with extra holes? (++ . - -)
http://www.amain.com/product_info.ph...es-74V-5800mAh