Batteries & Chargers Discuss Li-P, Li-Ion, NiMh, Nicad battery technology and the chargers that juice 'em up!

Can you wire Lipo packs in series?

Old 08-17-2006, 03:20 AM
Real Flying
Thread Starter
Epowerreg's Avatar
Join Date: Feb 2006
Posts: 204
Default Can you wire Lipo packs in series?

What would happen if you wired 2 -7.4v lipo packs in series? and could you charge them as an 14.8 v pack?
Epowerreg is offline  
Old 08-17-2006, 04:01 AM
Registered User
Twmaster's Avatar
Join Date: Aug 2005
Location: Dallas, TX, USA
Posts: 6,632

Twmaster is offline  
Old 08-17-2006, 06:20 AM
Kontrol Freak
Join Date: Aug 2005
Location: Melbourne, Australia
Posts: 136

I believe you would first need to ensure that both packs are individually balanced.
dimadee is offline  
Old 08-17-2006, 07:03 AM
Vamooska's Avatar
Join Date: Sep 2005
Posts: 105

Very much so..balancing is a must for that type procedure. Please also try to pick the same brand of packs. That is iffy at best. If you don' is what can happen. Good manufacturers will match cells for a pack. By that I mean they will compare internal resistance and discharge characteristics of all cells and match them with others as close to the same parameters as possible to assemble a pack. If you haphazardly throw cells together, chances are you will get a pack that has inherently different structures of cells and will hardly if ever, balance. When a pack is out of balance, the charging cycle can very easily lead to overcharged cells.....not good.
My advice is this. If you have a 3 cell pack and one cell puffs, make it a 2 cell pack. Go down in cell count and not up. That goes for parallel and series.
If you have any questions, PLEASE ask me.
Vamooska is offline  
Old 02-18-2007, 10:13 AM
New Member
Join Date: Feb 2007
Posts: 1

Yes but here is the thing...current WILL ALWAYS be exactly equal in series batteries, and parallel loads on equally charged identical battries with be equal except for minor random differences between theoretically identical battereis.

So what you say? Well Lithium BURNS very easily because it is a light element...AND these battries tend to get HOT if force current through them when they are completely discharged or over charged...bad the very least you ruin the battery for most types and at the most you have an explosion for conflageration on your hands. MUST have balanced charger for series batteries which will charge each indepentantly in identical ways. That takes care of the series part of the problem.

Now the second part can be a bit more touchy since not all supposedly identical batteries are actually identical, so they might have slightly different discharge characteristics...which doesn't matter much until you get to the end of the charge at which either ruin the battery or have an hot event.

This leads to a set of rules.

1) Most chargers do no anticipate batteries in parallel, and because you must use blanced charger to charge individual cells, you don't want them in parallel when you are charging. So charge each series set with a blanced charger designed for the set...each set SEPERATELY until COMPLETELY CHARGED at which time the charger will tell you things ar charged.

2) Use ONLY Identical sets of series batteries and CHARGE EACH SET SEPERATELY AND COMPLETELY using the SAME blanced charger to make the charging conditions as identical as possible.

3) THEN AND ONLY THEN connect them in parallel, ONLY WHEN IDENTICALLY CHARGED WITHOUT DISCHARGING ANY SET AT ALL...also it is a good idea to charge all sets without a great deal of seperation in time so that charge condition of sets don't change over time.

4) DON'T RUN THE BATTERIES COMPLETELY DOWN, but take care to use them so that you know there is some charge left...a significant drop in current availability or votage is a good sign you had better stop using the batteries IMMEDIATELY...until completely recharged again by the above safety procedures.
jjjsellers is offline  
Old 02-18-2007, 10:37 AM
Super Contributor
Join Date: Oct 2005
Location: N.Staffs, UK
Posts: 2,350

Originally Posted by Epowerreg View Post
What would happen if you wired 2 -7.4v lipo packs in series? and could you charge them as an 14.8 v pack?
Yes of course. That's all a 4S (14.8V) pack is, 4 cells wired in series.

But you'd be a fool to try it with anything other than 2 IDENTICAL packs.

slipstick is offline  
Old 02-24-2007, 06:20 PM
Purveyor of EPP goodness.
Tram's Avatar
Join Date: Dec 2005
Posts: 249

Yeh, you can, as the others have said wire them in series, however, like slipstick said, you would want to make sure it is 2 like packs.. I wouldn't wire a TP 3S 2100 and a CSRC 3S 2100 in series and feel comfortable with it..

Tram is offline  
Related Topics
Thread Starter
Last Post
Batteries & Chargers
01-21-2009 09:00 PM
Batteries & Chargers
10-17-2007 10:26 PM
Batteries & Chargers
02-11-2007 03:47 AM
Batteries & Chargers
10-12-2006 03:03 AM
Batteries & Chargers
12-24-2005 04:15 AM

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Quick Reply: Can you wire Lipo packs in series?

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service - Do Not Sell My Personal Information -

Copyright 2021 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.

Page generated in 0.08122 seconds with 13 queries