Lithium Polymer Noob Question

For a design project, we are using 3cell Li-Po battery packs which have two sets of wires coming off of the pack. I understand one is for
charging, the other is for discharging. From what I have read, I take it that the set of two (red/black) wires are for discharging and the set of multiple wires in a smaller white connector is for charging. If this assumption is correct, then what type of connector would I need to connect to an Astroflight 109 Li-Po charger? The connections off of the charger is the Astroflight zero loss connector.
Could someone please explain to me how I would connect these packs to the charger?
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snipped-for-privacy@gmail.com wrote:

The A109 charges through the two big red and black wires. You need a plug that fits the one on the battery. For safety reasons, the battery plug should be female. The smaller wires are for either a dedicated balancing charger or a balancer or a safety circuit. Depends on who manufactured your battery. Each maker puts on their own little plug which they buy from their brother in law. I suggest you read up on Lipo batteries on http://www.ezonemag.com
Fritz
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On 31 Jan 2006 14:16:08 -0800, snipped-for-privacy@gmail.com wrote:

The smaller white connector is for charging while monitoring voltage of each cell in the pack, and for balancing the pack (all cells to the same voltage within a few hundredths of a volt). The small white connector suggests PolyQuest to me. You can get a Protective Charge Module (PCM) from vendors of PQ batteries for about $14. It is a very good safety device that monitors the voltage on each cell, and shuts down charge current when any cell reaches 4.2 V. It goes between your Astro charger and the battery, and is the same sort of device built into lithium battery packs used in consumer appliances (e.g., cell phones), and is one the main reasons that such LiPo applications have a much better safety record than ours has. A balancer performs a similar function and also has the capability to bleed off charge from the cell(s) indicating the highest voltage, until the pack is balanced. It is more of a convenience than a PCM, as with the latter, the weaker cells need to be charged one at a time to bring it into balance. Strongly recommend using one these devices. Whatever the brand of your pack, somebody makes compatible charge adapters for use with PCM or balancer and your Astro charger.
Abel
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I appreciate your responses. Thanks for explaining the purpose of the smaller white connector. Everything makes sense now (I think).
So to charge my batteries, first I install appropriate connectors(female) on the red and black wires on the battery. These connectors would then plug into the charger? In short, basically charge through the red and black wires on the battery. :)
Please correct me if I am wrong.
One last thing to Fritz, I check out ezonemag.com and I was curious if there are any li-po guides or reading that you would suggest for a beginner like me.
Thanks again for all of your support!
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snipped-for-privacy@gmail.com wrote:

Yes..in the sticky section at the top of the batteries and chargers forum in the discussion group
Oh sod it. In here
http://www.rcgroups.com/forums/forumdisplay.php?f 9
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On 31 Jan 2006 17:38:00 -0800, snipped-for-privacy@gmail.com wrote:

I have a couple different brands of LiPos and they have different charging "methods". My TPs are like yours with the small white connector and the large connector (I soldered on a set of Deans) to the black/red wires. Those are charged off the black/red wire connector and I monitor the cells with a voltmeter through the small white plug.
My other LiPos have two JST plugs. One with red/black wires for discharge/operation and the other with white/black which is for charging only. (I *THINK* they're E-Flight branded) I assume the white/black JST plug is run through some sort of circuitry to balance the cells while charging.
Both brands come with a data/instruction sheet that outlines charge/discharge specs, proper handling/storage and warnings.
I also got a lot of good info out of my Triton charger's manual.
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On my Thunder Power 3 cell lipo the white connector with the multiple wires is for checking the balance of the individual cells and the other plug is for charging. There is really no reason to discharge a lipo in normal use unless you are trying to see if the battery still has its listed capacity or it is a new battery and you are trying to condition it on the first few cycles. I use an Accu-Cycle Elite for my charging duties and my 1320 cell has a JST connector on it and I have a JST to banana plug cable that goes to the charger.
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