Apr 19, 2009, 12:42 AM Registered User Joined Jan 2009 277 Posts Question do 2 3s lipos equal a 6s? I am going to build the new hangar 9 rv-8 with some hobbycity electronics. I know that if I join 2 3s lipos together it will just give me more flight time, right? But I need to conjoin two 3s packs with a conjoiner plug or something to equal the power of a 6s rather than buying a 6s lipo. is this possible? what is the difference between this a 6s2p? I notice the 6s2p is a solid 6s with one deans, and my charger only does up to 4s. And also with the 3s2p, it is only one 3s lipo. How do I conjoin two different lipos like an align 2150 mah 20c, and a rhino 2250 mah 30c to equal the power of a 4400mah 6s?
 Apr 19, 2009, 01:19 AM Registered User Knoxville, TN Joined Dec 2005 1,502 Posts http://hicountryhobbies.com/index.ph...products_id=65 This parallel adapter will make 2 3S1P 2200's into 1 3S2P 4400. http://hicountryhobbies.com/index.ph...products_id=66 This series adapter will make 2 3S1P 2200's in to 1 6S1P 2200. You could do what you are asking with two different packs in different sizes in parallel, making it a 3S 4400. But I am not sure you can put the two together to make a 6S 2200, I think not, but I could be wrong. It's my understanding, in series, the packs should be identical.(Someone correct me if I'm wrong) Not so in parallel, they can be varying sizes and C rating, just the voltage (cell count) must match. You can not, for sure, make them a 6S 4400 with those two packs. You would need two more packs even if it is possible to series connect those packs. With two packs you can either double the voltage (series) or double the capacity (parallel), but not both. And no, your charger if only 4S can not charge a 6S, but could do the 6S if made up of 2 3S, however it would have to charge them independently, or in parallel, but not in series. Confusing I know, but I hope that helps. Eric
 Apr 19, 2009, 01:30 AM Registered User So. Cal. Joined Oct 2004 8,927 Posts Eric is absolutely correct in that it is generally inadvisable to connect two lipoly packs in series unless they are identical in every way (IR, capacity, 'C' rating, manufacture, and usage history), especially if you have a tendency to depend on LVC to tell you when to land. The reason for this is that the lower capacity pack will likely hit termination voltage sooner and may overdischarge resulting in its demise. When connecting in parallel, cell count and charge state are the only important considerations. Capacity, 'C' rating, and usage history are not relevant, generally speaking. Unless this makes sense to you, it would be wiser and safer to use off-the-shelf packs. Mark
 Apr 19, 2009, 01:57 AM Registered User Knoxville, TN Joined Dec 2005 1,502 Posts I would agree, if these are packs that you are using in other airplanes, and want to double duty them connected in some way. Either do it in parallel, or don't even attempt a series setup. As Mark suggested, go buy the packs you need in the configuration you need them, or buy 2 packs to put in series that will only ever be used in that configuration. Some people will do that when 2 3S packs are cheaper than the single 6S pack. But either way it's buying new packs. IMO, paralleling packs is something a novice can pull of pretty easily with a little knowledge and some help from people with the proper experience. Using packs in series is something that only people who know exactly what they are doing should attempt to do. Eric
 Apr 19, 2009, 09:11 AM Registered User Joined Jan 2009 277 Posts OH!! perfect, thanks so much. So If I join 2 3s 2200 mah packs by parallel, I can have a 3s 4400 mah pack, and if by series, a 6s 2200mah. cool
 Apr 19, 2009, 08:18 PM Registered User Joined Jan 2009 277 Posts I already got my series conjoiner today. too bad I bought it before the plane, motor, esc, and servos.
 Apr 20, 2009, 08:29 PM Registered User Joined Jan 2009 277 Posts I didn't see any post not recommending it. you said it was easier to do, and works. first you say it's easy and any new person can do it, "IMO, paralleling packs is something a novice can pull of pretty easily with a little knowledge and some help from people with the proper experience." but then said, "Using packs in series is something that only people who know exactly what they are doing should attempt to do." is it easy or hard? the plug seems fairly simple to me. just a triangle shape, plug one in this end, plug that on the other end, and BAM!
Apr 20, 2009, 08:51 PM
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Parallelling is pretty easy, and has little chance at damaging your lipos.

As for series connecting, to repeat what mrforsyth said..

Quote:
 it is generally inadvisable to connect two lipoly packs in series unless they are identical in every way (IR, capacity, 'C' rating, manufacture, and usage history)
and..

Quote:
 Unless this makes sense to you, it would be wiser and safer to use off-the-shelf packs.
Parallel and series are VERY different and have drastically different consequences if the packs aren't identical in every way!

It isn't ill advised because the actual connecting process is difficult, in fact it's almost the same, just the configuration of the connector is different. It's the condition of the packs, voltage, output potential, and capacity that, if different, can damage your packs. In other words, it's recommended to only series connect 2 or more packs if they are exactly the same capacity, C rating, number of discharges, and charge state. A better way to say it might be, only series connect packs that were purchased for connecting in series, and have only ever been used in series connection.

Again, I'm only trying to help, but you are free to do as you please.
Eric
 Apr 20, 2009, 09:03 PM Suspended Account Joined Mar 2008 2,937 Posts ... Last edited by init4fun; Jul 27, 2009 at 12:33 PM.
Apr 20, 2009, 10:13 PM
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Joined Jan 2009
277 Posts
Quote:
 Originally Posted by EricJ320 Parallelling is pretty easy, and has little chance at damaging your lipos. As for series connecting, to repeat what mrforsyth said.. and.. Parallel and series are VERY different and have drastically different consequences if the packs aren't identical in every way! It isn't ill advised because the actual connecting process is difficult, in fact it's almost the same, just the configuration of the connector is different. It's the condition of the packs, voltage, output potential, and capacity that, if different, can damage your packs. In other words, it's recommended to only series connect 2 or more packs if they are exactly the same capacity, C rating, number of discharges, and charge state. A better way to say it might be, only series connect packs that were purchased for connecting in series, and have only ever been used in series connection. Again, I'm only trying to help, but you are free to do as you please. Eric
Actually, I am using 4 identical in everyway hobbycity lipos to make two sets for it. the are all 20c 2200mah 3s, and should all com in at the same time soon.
Apr 20, 2009, 10:30 PM
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Well you didn't say that. This was the last reference you made to pack type.

Quote:
 How do I conjoin two different lipos like an align 2150 mah 20c, and a rhino 2250 mah 30c to equal the power of a 4400mah 6s?
In light of this new info, you should be fine, just be careful and make sure to properly monitor your batteries and setup with an appropriate watt meter.

Eric
Apr 20, 2009, 11:20 PM
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Quote:
 Originally Posted by EricJ320 Well you didn't say that. This was the last reference you made to pack type. In light of this new info, you should be fine, just be careful and make sure to properly monitor your batteries and setup with an appropriate watt meter. Eric
thanks. I have a wattmeter too. I'm not that much of a newbie.
Apr 20, 2009, 11:24 PM
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Joined Jan 2009
277 Posts
Quote:
 Originally Posted by EricJ320 Well you didn't say that. This was the last reference you made to pack type. In light of this new info, you should be fine, just be careful and make sure to properly monitor your batteries and setup with an appropriate watt meter. Eric
I used those batts that I had as an example, but did order the 4 hc lipos about a week ago, just my example. I can as easily use my new hc ones.