Espritmodel.com Telemetry Radio
Reply
Thread Tools
Old Apr 05, 2005, 09:26 AM
Southern Pride
everydayflyer's Avatar
Haralson County GA. USA
Joined Oct 2004
34,557 Posts
To parallel Li Poly batteries of the same number of cells just fly them to the same LVC or check their voltages to verify that they are approximately the same voltage,as in not mixing mostly fully charged with mostly fully discharged. Connect them in parallel,
FMA Direct has a 5 connector strip ,both parallel and series ones. I use a parallel one with my AF 109 to charge up to 5 ,1200 mAh 3S Li Poly batteries often. I charge at up to 6amps. and have 5 batterues ready to fly in a little over one hour.You can do the same thing with a Triton,Apache 2500,TP425 or other Li Poly chargers the limit being the max. amp(charge rate) of the charger..Li Poly batteries charge just fine in series/paralled configurations.
If you are parallel charging packs of the same number of cells (must be)but of different capacities such as a mix of 700s and 1200s then you would have to charge at the max rate for the lowest capacity pack(s). In this case it would be .7A (700 mA)..

Charles
everydayflyer is offline Find More Posts by everydayflyer
Reply With Quote
Sign up now
to remove ads between posts
Old Apr 05, 2005, 09:34 AM
Registered User
unbalanced prop's Avatar
Washington, PA, USA
Joined Aug 2003
1,486 Posts
Thanks Charles

I'll have to check out that parallel strip from FMA Direct. Sounds like an easy way to charge multiple packs.

Doug
unbalanced prop is offline Find More Posts by unbalanced prop
Reply With Quote
Old Apr 05, 2005, 10:21 AM
Unregistered User
Alex Titoff's Avatar
Limassol, Cyprus
Joined Oct 2003
150 Posts
Charles, is this one http://www2.towerhobbies.com/cgi-bin...=++&search3=Go ok for this job?
Alex Titoff is offline Find More Posts by Alex Titoff
Reply With Quote
Old Apr 05, 2005, 10:56 AM
Cal
Registered User
Cal's Avatar
San Gabriel, California
Joined Aug 2004
1,583 Posts
The Accu-Cycle Elite will charge two lipo packs at the same time.........

Here's a review: http://www.rcuniverse.com/magazine/a...article_id=405
Cal is offline Find More Posts by Cal
Reply With Quote
Old Apr 05, 2005, 01:13 PM
Southern Pride
everydayflyer's Avatar
Haralson County GA. USA
Joined Oct 2004
34,557 Posts
Quote:
Originally Posted by Alex Titoff
Charles, is this one http://www2.towerhobbies.com/cgi-bin...=++&search3=Go ok for this job?
Yes ,that's the one I use.

Charles
everydayflyer is offline Find More Posts by everydayflyer
Reply With Quote
Old Apr 05, 2005, 01:18 PM
Unregistered User
Alex Titoff's Avatar
Limassol, Cyprus
Joined Oct 2003
150 Posts
Quote:
Originally Posted by everydayflyer
Yes ,that's the one I use.

Charles
Hm! They say in the COMMENTS:
Do not connect Li-Po batteries of different capacity or voltage
ratings to the parallel boards simultaneously.
Do not connect Li-Po batteries of different charge conditions to the
parallel boards simultaneously.

Shall I discard this warning? I am really afraid to ignite the packs.
Alex Titoff is offline Find More Posts by Alex Titoff
Reply With Quote
Old Apr 05, 2005, 01:47 PM
Southern Pride
everydayflyer's Avatar
Haralson County GA. USA
Joined Oct 2004
34,557 Posts
Quote:
Originally Posted by Alex Titoff
Hm! They say in the COMMENTS:
Do not connect Li-Po batteries of different capacity or voltage
ratings to the parallel boards simultaneously.
Do not connect Li-Po batteries of different charge conditions to the
parallel boards simultaneously.

Shall I discard this warning? I am really afraid to ignite the packs.
I do not take Li Poly charging or useage safety lightly. I understand the reason s for the warnings. It is perfectly safe to connect Li Poly packs of the same cell count which are in approximately the same state of charge in parallel for charging. If you were connecting them in series for flight they would have to be witin 0.01 volts of each other.I have found that for charging in parallel that withing 0.2 of a volt is plenty close enough. I use my AF109 charger. I check packs volts with a DVM. I connect the packs to strip start charge with charger set to zero as per users manual. I increase charge rate to approximately 0.2C (for the combined total mAh connected).After second stage starts I slower increase the charge rate until 1C max is reached.If you feel uncomfortable then do not do it. It has worked for me on may occasions.
FMA (Kokam) did a test with a very small capacity and a very large capacity battery connected in parallel and after something like 750 cycles one cell went out of balance.

Read some of post in the Thread here.

Now look at the date that thread was started and by who.
Charlesi
everydayflyer is offline Find More Posts by everydayflyer
Last edited by everydayflyer; Apr 05, 2005 at 02:06 PM. Reason: corrected series volts
Reply With Quote
Old Apr 06, 2005, 09:16 AM
Does anyone hear a cat?
headless's Avatar
Tallahassee, FL
Joined Sep 2003
4,380 Posts
Hey all, just wanted to post that i also charge multiple packs in parallel on a single output from my charger. I fly small tp480 packs in most of my planes, and own 7 of them. I charge up to 5 at once with a simple parallel charging harness. As everydayflyer has mentioned, as long as you plug them together in parallel while voltages are relatively close (anything under .3v is good to go if the voltages of both packs are somewhere under 11.2v in my humble opinion) you can simply charge them up. I charge 5 tp480's at once at 2.5amps without incident and have been for a couple of months now (i hate making wiring harnesses )
headless is offline Find More Posts by headless
Reply With Quote
Old Apr 06, 2005, 09:23 AM
Omnipote
stone_axe's Avatar
Louisville, KY
Joined Apr 2001
665 Posts
I am really happy with my Hobbico Dual field charger.
http://www2.towerhobbies.com/cgi-bin...&I=LXCTZ5&P=ML

It's cheap and it does my Nickel batteries too. The downside is that it's limited to 1a for Lithium charging and it only brings the packs to a more modest voltage compared to some of the other chargers. I don't mind that at all, I'm more concerned in protecting pack longevity than eeking out another 10% of capacity.
stone_axe is offline Find More Posts by stone_axe
Reply With Quote
Reply


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Discussion Whats the best lipo charger to charge multiple packs? marcwv Batteries and Chargers 13 Aug 29, 2007 02:31 AM
I need a cheap Lipo charger that will not explode my cells. roundthebend Micro Helis 9 Oct 03, 2005 05:34 PM
Cascade Charger that will charge your battery automatically as many packs as you wish cadetman Batteries and Chargers 8 Feb 08, 2005 02:12 AM
Charger that will charge 2 NiMh's or 2 Lipo's at the same time? Tram Batteries and Chargers 3 Oct 12, 2004 07:28 PM
Least expensive Li-Po charger that will charge a 3s1p Etec? The Blue Max Batteries and Chargers 18 Oct 02, 2003 09:33 PM