HobbyKing.com New Products Flash Sale
Reply
Thread Tools
Old Jan 05, 2009, 12:41 PM
Registered User
badger-b's Avatar
UK
Joined Jul 2008
391 Posts
Lol
badger-b is offline Find More Posts by badger-b
Reply With Quote
Sign up now
to remove ads between posts
Old Jan 07, 2009, 09:29 PM
Registered User
tap135's Avatar
United States, PA, Perkasie
Joined Dec 2008
472 Posts
Hi all, And Thanks for giving me a lot of posts to read. As well as a lot of info to absorb.

My question is this. Where can I get the connectors that everyone is using? I believe someone mentioned silicon wiring in a post? I would assume that staying with the normal wiring/gauge values would be sufficient?

Will need Aline, JST & dean connectors.

Any links would be appreciated.

Another question came up after my originial posting.

From another source - I was told that I can use the balance connectors to charge in parallel and I would then increase the voltage and NOT the amperage.

Now I don't play with rockets nor own a lab coat. But an out of practice tech/electrician. This does not make sence to me. Because everything I remember and what I've read here says otherwise.

Thanks
Tom
tap135 is offline Find More Posts by tap135
Last edited by tap135; Jan 08, 2009 at 11:38 AM.
Reply With Quote
Old Jan 08, 2009, 02:19 PM
Proud to eat Kraut ;-)
Julez's Avatar
Germany
Joined Dec 2003
5,326 Posts
Quote:
I was told that I can use the balance connectors to charge in parallel and I would then increase the voltage and NOT the amperage.
You are right - that statement is plain wrong.
Julez is offline Find More Posts by Julez
Reply With Quote
Old Jan 08, 2009, 02:30 PM
Registered User
Joined Nov 2008
535 Posts
Quote:
Originally Posted by tap135
I was told that I can use the balance connectors to charge in parallel and I would then increase the voltage and NOT the amperage.
That would be charging in series, not parallel.

There's still very real risk in hooking things up wrong. Hooked up right, and too a good balancing charger, it is probably safer than parallel charging, as each cell's charging is somewhat individually supervised, and that they cannot directly charge each other out of the control of the charger. But again, the risk of hooking it up improperly remains.
cstratton is offline Find More Posts by cstratton
Reply With Quote
Old Jan 08, 2009, 04:18 PM
Registered User
tap135's Avatar
United States, PA, Perkasie
Joined Dec 2008
472 Posts
Ok, then if I did charge with the balancing connectors- in series, I do not need the other JST connector. And I would increase the voltage not the amps.

Time difference?

And the risk is understood, as far as I am concerned anything dealing with LiPo's seems to be a risk. That is whyI stopped at Home Depot and bought my battery bunker.

Thanks
Tom
tap135 is offline Find More Posts by tap135
Reply With Quote
Old Jan 08, 2009, 05:04 PM
Registered User
badger-b's Avatar
UK
Joined Jul 2008
391 Posts
Quote:
Originally Posted by tap135
Ok, then if I did charge with the balancing connectors- in series, I do not need the other JST connector. And I would increase the voltage not the amps.

Time difference?

And the risk is understood, as far as I am concerned anything dealing with LiPo's seems to be a risk. That is whyI stopped at Home Depot and bought my battery bunker.

Thanks
Tom
But then you are NOT parallel charging you are connecting them in series.
Say for instance you had 3 x 3 s packs and connected these in series via the main leads, you end up with one 9S pack, and each 4 pin balance tap would need to be correctly harnessed in order to reflect that configuration of cells. Apart from the high voltage your charger would then need to deliver, this method is NOT what this thread is really all about, and connecting 3 packs of differing states, and capacities etc in series is not recommended.
I think you need to gen up a bit more on pack configurations and makeup
badger-b is offline Find More Posts by badger-b
Reply With Quote
Old Jan 08, 2009, 05:08 PM
Registered User
Joined Nov 2008
535 Posts
The balancer would not be able to do cell-level balancing of a series connection of packs, unless the packs being connected were only one cell each, and the total number of packs were compatible with the number of cells the charger has balance connections for.

Unlike in a parallel connection, the charger has a greater chance of being able to detect faults and shut down. And in theory there's no source of charge current other than the charger, so if the charger shuts down the process should stop.

Contemplate for a minute what happens if an mCX battery is connected backwards (Eflight has a warning about this blowing heli rx's, so apparently it happens) into a series gang charging setup built leveraging the balancing taps, vs. a parallel gang charging setup. Not something you want to have happen, but the failure modes in the series case look better to me.
cstratton is offline Find More Posts by cstratton
Reply With Quote
Old Jan 09, 2009, 08:07 AM
Registered User
Melbourne, Australia
Joined May 2006
6,407 Posts
Quote:
The balancer would not be able to do cell-level balancing of a series connection of packs, unless the packs being connected were only one cell each,
Poppycock! I have series balance charged 2 x 2S packs as 4S, 2 x 3S packs as 6S, 2 x 4S as 8S and 2 x 5S as 10S many, many times, you simply need the appropriate adapter/harness for the balance leads in addition to a series harness for the main power leads. I have a setup that can balance charge 4 x 2s = 8s, 2 x 3s = 6s, 3 x 3s = 9s, 2 x 4s = 8s and 2 x 5s = 10s. Anyway, that is serial charging and not what this thread is about which is a safe way to do parallel charging.
kgfly is offline Find More Posts by kgfly
Reply With Quote
Old Jan 10, 2009, 08:20 AM
Registered User
Joined Nov 2008
16 Posts
Quote:
Originally Posted by cstratton
The balancer would not be able to do cell-level balancing of a series connection of packs, unless the packs being connected were only one cell each, and the total number of packs were compatible with the number of cells the charger has balance connections for.
Oh man. There is always one in every crowd.
Not only are you a wet blanket, your information is absolutely WRONG.
Everyone here knows the risk LiPo batteries present.
There are risks in everything that we do.
Every time I fire up a heli there are saftey risks.

Go find an old nanny's thread and bug them instead.
Heliwrecker is offline Find More Posts by Heliwrecker
Reply With Quote
Old Jan 10, 2009, 10:01 AM
Registered User
Joined Nov 2008
535 Posts
Quote:
Originally Posted by Heliwrecker
Not only are you a wet blanket, your information is absolutely WRONG.
No, it is you who are mistaken. What I posted is absolutely 100% factual - a balancer cannot do cell-level balancing unless it is connected to each individual cell.

Note that the situation being described was one of a series connection of cells - without a balancing tap at each joint between the series cells, balance charging is not possible. This is no less true for packs connected in series than it is for a multi-cell pack of cells assembled in series - without balancing taps, you can't balance charge.

The minute you build a setup where each balance tap is spanning more than one cell in series, you can no longer balance those cells. As far as those cells are concerned, they are in a two (or whatever) cell pack connected to a non-balancing charger. The pair may get balanced as a unit compared to another pair, but the two cells of the pair are cannot be balanced relative to each other.

Nor can a charger handle more 1-cell packs in series than it can handle cells in a single series-connected pack.
cstratton is offline Find More Posts by cstratton
Last edited by cstratton; Jan 10, 2009 at 10:07 AM.
Reply With Quote
Old Jan 10, 2009, 11:02 AM
ProgressiveRC
write2dgray's Avatar
Seattle, WA
Joined Dec 2006
1,997 Posts
Not sure if this clears anything up for anyone, but here's a graph of a pair of 3S lipos charged in series with per cell voltage monitored and balanced:

http://www.rcgroups.com/forums/showt...6#post10726986

I think this has been mentioned before, but that is not the point of this thread is not recommended for lipos that don't have similar history and are not discharged in series. Parallel charging is highly advised over series charging if you are seeking to charge multiple lipos simultaneously. Series charging does allow for graphing/balancing of individual cells, but this same feat is accomplished in parallel in all practicality since cells connected in parallel quickly level to identical voltage.

- David
write2dgray is offline Find More Posts by write2dgray
RCG Plus Member
Reply With Quote
Old Jan 10, 2009, 11:03 AM
Registered User
badger-b's Avatar
UK
Joined Jul 2008
391 Posts
Quote:
Originally Posted by cstratton
No, it is you who are mistaken. What I posted is absolutely 100% factual - a balancer cannot do cell-level balancing unless it is connected to each individual cell.

Note that the situation being described was one of a series connection of cells - without a balancing tap at each joint between the series cells, balance charging is not possible. This is no less true for packs connected in series than it is for a multi-cell pack of cells assembled in series - without balancing taps, you can't balance charge.

The minute you build a setup where each balance tap is spanning more than one cell in series, you can no longer balance those cells. As far as those cells are concerned, they are in a two (or whatever) cell pack connected to a non-balancing charger. The pair may get balanced as a unit compared to another pair, but the two cells of the pair are cannot be balanced relative to each other.

Nor can a charger handle more 1-cell packs in series than it can handle cells in a single series-connected pack.
Not sure which post you refer to there cstratton - but in my reply to TAP135 and his question about charging his packs in series, I pointed out that this thread was about parallel charging anyway, but that IF he wanted to charge in series AND be balanced, then "a suitable harness would need to made to ensure that the balance taps were correctly configured" - thats exactly the point - IF the taps were connected correctly, then each cell in his 9s pack could be accessed by the balancer ( assuming a 9s / 10s socket ) and therefore balanced.
badger-b is offline Find More Posts by badger-b
Reply With Quote
Old Jan 10, 2009, 04:05 PM
Boffin
rpage53's Avatar
Victoria, BC, Canada
Joined Apr 2001
3,397 Posts
Quote:
Ok, then if I did charge with the balancing connectors- in series
Tap135 asked about connecting the balancing taps in series and using them to charge. That is just a very bad idea and doesn't require any discussion. Don't do it.

Rick.
rpage53 is offline Find More Posts by rpage53
Reply With Quote
Old Jan 11, 2009, 10:02 AM
Registered User
Joined Nov 2008
535 Posts
Quote:
Originally Posted by rpage53
Tap135 asked about connecting the balancing taps in series and using them to charge. That is just a very bad idea and doesn't require any discussion. Don't do it.
Charging a series array of cells with the main connectors and balancing taps is their intended purpose, so perhaps you want to rethink or reword your comment. If your concern was that only the balancing taps might be be going to be used, then say that.

Yes, there is substantial risk in temporary assembling any array of cells for charging, but the consequences of likely errors (open circuit or reverse polarity) are lower in the series case. Similarly, assembling unmatched cells for charger results in a badly balanced 'pack' - but in the series case the charger controls the resolution of this, while in the parallel it occurs with no means of monitoring or intervention.
cstratton is offline Find More Posts by cstratton
Reply With Quote
Old Jan 11, 2009, 12:03 PM
The Great Santini
Santini's Avatar
Madison, NJ 07940
Joined Dec 2004
1,922 Posts
Nice Thread. I'm considering trying parallel charging.
Packs: 3s 2200 packs
Brands: TP, Xcite, EVO
Charger: TP610C (80 watts) w BL2 balancing board, and 20amp powerforce ps
Objective: 3 in parallel

I've read and understand the basics, and know I need to make/buy a (deans) parallel charging lead. No problem. My questions are on the balancing leads and are based on various posts and pics in this thread and its links:

1) BL2 balancing Board. What are my options (if any) using this board alone (attached)? Specifically:

a) Are the PQ style taps on the BL2 in parallel such that I could plug more than one batt at a time into this section of the board and obtain a parallel connection, similar to what was depicted here with the icharger board for TP taps? (In this case, I would be using the first pins in three slots 3S-5S on the BL2).

b) Using the BL2, is it possible to mix battery tap types, and get a parallel for two at once , such as the TP tap and the PQ (Xcite) taps? Basically use the TP tap and one or more of the others at the same time?

2) Can you point me to boards that would be compatible with the 610C that would enable mutliple packs in parallel like in the link above?

3) Are there any premade three lead parallel taps (or twos) that I could simply plug into the appropriate plug on the Board? All I could find was this and this? Yes?

So, as you can see, I am at the "OK, but how to, exactly?, stage". Maybe you can help me out, someone, thanks.
Santini is offline Find More Posts by Santini
Reply With Quote
Reply


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
what is safer series or parallel charging of multi lithium packs? BING! Batteries and Chargers 13 Nov 10, 2003 07:04 PM
Re lithium and parallel charging Vanier Power Systems 1 Aug 12, 2003 02:40 AM
Parallel charging with isolation diodes? HankF Batteries and Chargers 4 Jan 05, 2003 05:22 PM
A Question About Slow Charging New NiMH Batteries? Coyoteair Electric Heli Talk 1 Jan 31, 2002 12:02 PM