Thread Tools
Old May 08, 2016, 11:12 PM
xibriz is offline
Find More Posts by xibriz
Registered User
Joined May 2016
16 Posts
Help!
Lipo in series

First off, I'm not new to lipos. I have had them in cars for a long time, I know how to charge them and all that. Two of my cars run lipos in parallel.

What I don't have experience with is lipos in series.

I have a ebike project that I want do run lipos on with the following requirements/restrictions:

- I only have a 6S charger
- I need minumum 48V, max 60V.

I have figured out that 14S would be perfect.

So I'm thinking:
1x Multistar High Capacity 6S 16000mAh Multi-Rotor Lipo Pack
2x Multistar High Capacity 4S 16000mAh Multi-Rotor Lipo Pack

In series. Would this work without any (life threatening) problems?

I know this is a RC forum, but most of the people on the ebike forum are really afraid of lipos. Maybe they have stocks in 18650 cells.
xibriz is offline Find More Posts by xibriz
Last edited by xibriz; May 08, 2016 at 11:38 PM.
Reply With Quote
Sign up now
to remove ads between posts
Old May 08, 2016, 11:59 PM
xibriz is offline
Find More Posts by xibriz
Registered User
Joined May 2016
16 Posts
Also I know the specs of the batteries have to be the same. The specs of the batteries I have listed:

Minimum Capacity: 16000mAh
Configuration: 4S2P / 14.8V / 4Cell
Constant Discharge: 10C
Peak Discharge (10sec): 20C
Pack Weight: 1290g
Pack Size: 173 x 74 x 45mm
Charge Plug: JST-XH
Discharge Plug: XT90


Minimum Capacity: 16000mAh
Configuration: 6S2P / 22.2V / 6Cell
Constant Discharge: 10C
Peak Discharge (10sec): 20C
Pack Weight: 1920g
Pack Size: 173 x 74 x 68mm
Charge Plug: JST-XH
Discharge Plug: XT90
xibriz is offline Find More Posts by xibriz
Reply With Quote
Old May 09, 2016, 04:25 AM
xibriz is offline
Find More Posts by xibriz
Registered User
Joined May 2016
16 Posts
I'm assuming that each pack has two and two cells in parallel, so I can't really see any problems.

Please confim/disprove my assumptions
xibriz is offline Find More Posts by xibriz
Reply With Quote
Old May 09, 2016, 04:36 AM
Mark Wood is offline
Find More Posts by Mark Wood
characters welcome!
Mark Wood's Avatar
United States, CA, Bear Valley Springs
Joined Feb 2000
27,713 Posts
Sure. Charge packs in parallel, discharge in series.
Same cells, packs are all matched. Shouldn't be a problem.

mw
Mark Wood is offline Find More Posts by Mark Wood
Reply With Quote
Old May 09, 2016, 06:28 AM
slipstick is offline
Find More Posts by slipstick
Registered User
Staffs, UK
Joined Nov 2003
12,353 Posts
Errr...I wouldn't try charging 6S and 4S packs in parallel .

But other than that there's no real problem. Charge the packs individually and then use them in series. They should be fine.

Steve
slipstick is offline Find More Posts by slipstick
Reply With Quote
Old May 09, 2016, 07:04 AM
xibriz is offline
Find More Posts by xibriz
Registered User
Joined May 2016
16 Posts
I agree about not charging all the packs in parallel.

I was thinking to charge all individually or the two 4S in parallel.
Maybe I will need to get a bigger charger.
I only have one 1x50w charger and one 4x50w charger.
xibriz is offline Find More Posts by xibriz
Reply With Quote
Old May 09, 2016, 07:35 AM
ggcrandall1 is online now
Find More Posts by ggcrandall1
Registered User
ggcrandall1's Avatar
USA, GA, Marietta
Joined Aug 2005
8,351 Posts
Quote:
Originally Posted by xibriz View Post
I agree about not charging all the packs in parallel.

I was thinking to charge all individually or the two 4S in parallel.
Maybe I will need to get a bigger charger.
I only have one 1x50w charger and one 4x50w charger.
A 4S 16000mAh pack requires 268W for a 1C charge.
A 6S 16000mAh pack requires 403W for a 1C charge.

May I suggest you need a 1000W charger. You could charge the two 4S in parallel at 2C and get it done in about 30 minutes. Charge the 6S by itself at 2C also in about 30 minutes. So you could get the whole thing done in little over an hour.

The PowerLab 6 is 1000W;
http://www.usastore.revolectrix.com/...-EC5-version_2

This would be the power supply for it.
http://lipoconnectionsolutions.com/H...HP24V1500W.htm

Glen
ggcrandall1 is online now Find More Posts by ggcrandall1
Reply With Quote
Old May 09, 2016, 09:56 AM
Mark Wood is offline
Find More Posts by Mark Wood
characters welcome!
Mark Wood's Avatar
United States, CA, Bear Valley Springs
Joined Feb 2000
27,713 Posts
Quote:
Originally Posted by slipstick View Post
Errr...I wouldn't try charging 6S and 4S packs in parallel .

But other than that there's no real problem. Charge the packs individually and then use them in series. They should be fine.

Steve
Oops. Thanks, Steve. I forgot about the 6s. Parallel charging the 2 4s packs is fine.

mw
Mark Wood is offline Find More Posts by Mark Wood
Reply With Quote
Old May 09, 2016, 11:17 AM
kamcoman is online now
Find More Posts by kamcoman
Registered User
Douglasville, GA
Joined Sep 2004
581 Posts
Here are two other 1000-watt chargers, both with Junsi programming.
http://www.hobbypartz.com/75p-1030-charger.html
http://www.hobbyking.com/hobbyking/s...Search=reaktor
These have the same functions (and software, I think) as an iCharger 3010b
The LipoConnection power supplies are great.
kamcoman is online now Find More Posts by kamcoman
Reply With Quote
Old May 09, 2016, 12:42 PM
vollrathd is online now
Find More Posts by vollrathd
Registered User
vollrathd's Avatar
United States, WI, Racine
Joined Jan 2007
3,493 Posts
Quote:
Originally Posted by xibriz View Post
I agree about not charging all the packs in parallel.

I was thinking to charge all individually or the two 4S in parallel.
Maybe I will need to get a bigger charger.
I only have one 1x50w charger and one 4x50w charger.
Yeah, you need a new charger. It will take some 5 hours to charge one pack with that 50 Watt charger.

Cellpro's are very good units. I have a pair of PL8's.
vollrathd is online now Find More Posts by vollrathd
Reply With Quote
Old May 11, 2016, 05:05 AM
xibriz is offline
Find More Posts by xibriz
Registered User
Joined May 2016
16 Posts
Thanks for all your inputs.

I had to buy the only charger in stock at HK (EU Warehouse), the TURNIGY MEGA 1344W / 40A Balance Charger / Discharger.

Since I dont live in the US, I will have a friend make me a powersupply from a Toroidal Transformer (230V -> 24V).

Or maybe I will just use a 12V >600W computer PSU. As I understand it the chargher will up the out Voltage on is own?
xibriz is offline Find More Posts by xibriz
Last edited by xibriz; May 11, 2016 at 05:18 AM.
Reply With Quote
Old May 11, 2016, 06:04 AM
slipstick is offline
Find More Posts by slipstick
Registered User
Staffs, UK
Joined Nov 2003
12,353 Posts
You'll do better to use a server power supply. They are easily available and there are several threads in this forum about converting them.

But you'll find that although the charger does up the voltage for you there is probably a limit to how much power it can use with only 12V for input.

Steve
slipstick is offline Find More Posts by slipstick
Reply With Quote
Old May 11, 2016, 07:17 AM
fishfiend is offline
Find More Posts by fishfiend
Registered User
Joined Jun 2008
492 Posts
If you get the 1000w reaktor from HK you could use 7s packs..just saying
.
fishfiend is offline Find More Posts by fishfiend
Reply With Quote
Old May 11, 2016, 07:39 AM
xibriz is offline
Find More Posts by xibriz
Registered User
Joined May 2016
16 Posts
Quote:
Originally Posted by fishfiend View Post
If you get the 1000w reaktor from HK you could use 7s packs..just saying
.
Yeah I know. But the 6S and 4S packs was on sale Almost half price.

I am also in luck, I found two Artesyn 7000758-0002 laying around at work (I work in IT). Now I only need to figure out how to hook them up.
xibriz is offline Find More Posts by xibriz
Reply With Quote
Old May 11, 2016, 11:47 AM
E-Challenged is offline
Find More Posts by E-Challenged
Registered User
E-Challenged's Avatar
United States, CA, Garden Grove
Joined Oct 2000
14,170 Posts
If all of your packs are new and have the same individual cell capacities you should be able to charge and use them connected in series. I would want a charger that displays 7 individual cell voltages and properly balance charges them and monitor charging and cell balance. Also good to have readout of individual cell resistance and watch for large deviations. Be careful not to discharge cells below storage charge levels. Use some sort of a wattmeter to avoid too heavy discharge amp rates for battery when underway as when accelerating, and climbing grades.

I use a mobility scooter with two 12 volt 18 amp rated sealed lead acid batteries in series for 24 volts. I avoid over-discharging keeping charge levels in the green on the battery condition meter. The stock charger is designed not to overcharge batteries when left connected. It might be a lot cheaper and safer to use SLA batteries in your application if you can carry the weight.
E-Challenged is offline Find More Posts by E-Challenged
Last edited by E-Challenged; May 11, 2016 at 12:53 PM.
Reply With Quote


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Discussion 2 x 3S lipos in series vs 1 x 6S lipo? GodsLt Batteries and Chargers 8 Mar 29, 2016 11:58 AM
Question Cell monitor for lipos in series ronaldopn Batteries and Chargers 6 Dec 23, 2015 12:03 PM
Discussion Different Number of Lipo Cells in Series E-Challenged Batteries and Chargers 3 Nov 25, 2015 01:14 PM
Discussion Do I have this right about connecting 3s 3000mah lipo batteries in series? G.F. Beurling Batteries and Chargers 8 Nov 18, 2015 12:32 PM
Discussion 12S 5000 setup...3 lipos in series versus 2 lipos in series racin06 Power Systems 7 Dec 16, 2012 05:50 PM