Dead 4600mah A123 pack after 4 charges?  
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All Forums >> Radios, Batteries, Clubhouse and more >> Batteries & Chargers >> A123Racing Support >> Dead 4600mah A123 pack after 4 charges?
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Dead 4600mah A123 pack after 4 charges? - 6/23/2008 2:32:55 AM   
fb5b


 

Posts: 10
Joined: 6/23/2008
From: , AUSTRALIA
Status: offline 		Hi I have a A123 racing premade 2S2P pack that I believe is dead after 4 cycles. I use their Hypersonic charger to charge it and it always had issues on balancing this pack, when I emailed them they gave me a vague "oh on the first time it may take a while" answer, the pack got unusually warm during a run yesterday in an E-Savage running 2 of these packs, and when I stopped, I tested the voltage at 3.6 volts total (the other pack was at 6 volts) Upon trying to recharge one cell in particular got VERY warm, other pack charged up fine.

Is this common?

Have spent $300 in total on these, the charger etc and can't even get an email out of A123racing right now.

       Post #: 1

RE: Dead 4600mah A123 pack after 4 charges? - 6/23/2008 2:46:48 AM   
snellemin



Posts: 738
Joined: 3/22/2007
From: Tomball, TX, USA
Status: offline 		I have bought a few A123 packs that did not balance right when I first got them and charged them on my Hypersonic charger. I used a A123 Blinky and a homemade balancer connector to balance all the cells. The only thing you can do really is open up the battery pack and solder on balancing wires and see if the cells can be recovered with a slow charge.

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Snelle-RC, A123 Racer

(in reply to fb5b)
       Post #: 2

RE: Dead 4600mah A123 pack after 4 charges? - 6/23/2008 3:12:24 AM   
fb5b


 

Posts: 10
Joined: 6/23/2008
From: , AUSTRALIA
Status: offline 		But should I have to? I mean I spend big $$ on their proprietory charger, balancing system etc and they can't even return an email?

(in reply to snellemin)
       Post #: 3

RE: Dead 4600mah A123 pack after 4 charges? - 6/23/2008 3:27:15 PM   
Walt Thyng


 

Posts: 754
Joined: 7/27/2002
From: St. Charles, IL, USA
Status: offline 		fb5b,

a lot of us have found that immediately after a charge (even with a balancer) A123 cells are still all over the place. Check them 12-24 hours later and they are within .01.
WT

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WT in Illinois

(in reply to fb5b)
       Post #: 4

RE: Dead 4600mah A123 pack after 4 charges? - 6/23/2008 5:34:02 PM   
dirtybird


 

Posts: 3031
Joined: 1/25/2002
From: Mesa, AZ, USA
Status: offline 		I have found the cells are not of consistant quality. So far I have lost a total of 11 cells, five to my own inattention. If you charge one to more than 4.2 volts you will ruin it. It will get hot and after that it will be shorted.
Contrary to popular notion they must be balanced. They will not balance themselves. If you don't, you are likely to overcharge one and ruin it.
I have lost 6 cells by simply cycling them within the specificstions. They short out after a cycle.
The sells I lost are of questionable history. I bought four from a friend. Who knows what he did to them. The others came from a DeWalt pack I bought about a year ago.
They are a lot more fragile than I was led to believe. Save your receipts.

(in reply to Walt Thyng)
       Post #: 5

RE: Dead 4600mah A123 pack after 4 charges? - 6/23/2008 6:27:19 PM   
everydayflyer



Posts: 932
Joined: 8/21/2005
From: Buchanan, GA, USA
Status: offline 		Yes ther customer service or lack there of sucks. they have one person who checks this Forum every once in a great while.

I never thought much of their charger or their premade packs as they are overpriced and to limited IMO.

I do love their cells however. I have close to 100 cels made up in 3S - 5S packs and some new cells waiting for some of the others to ever wear out. I have one 3S with over 450 flights on it many 4S with over a hundred flights on them a 5S with close to 100 flight on them. In two years and over 1500 flights and 300 run in a RC Truck I have only managed to kill on cell and that was completely my faault.

I build my own packs,I always add balancing taps and I balance charge for the first 5-15 cycles until the cells settle down (form) . I do the first few charges at 5 amps. then start increasing the rate with each charge. I routinely charge 4 and 5S packs at 10 amp. and the 3S s get charged at an avergae 20 amp. rate.


Charles

< Message edited by everydayflyer -- 6/23/2008 6:29:18 PM >

(in reply to dirtybird)
       Post #: 6

RE: Dead 4600mah A123 pack after 4 charges? - 6/23/2008 6:44:27 PM   
dirtybird


 

Posts: 3031
Joined: 1/25/2002
From: Mesa, AZ, USA
Status: offline 		Where do you get your cells?

(in reply to everydayflyer)
       Post #: 7

RE: Dead 4600mah A123 pack after 4 charges? - 6/23/2008 7:22:00 PM   
everydayflyer



Posts: 932
Joined: 8/21/2005
From: Buchanan, GA, USA
Status: offline 		Mostly from DeWalt 36 V cordless batteries purchased off of E Bay.. They were approx. $90 to $100 shipped up to around 8 months ago and they went to around $120 to $140. I have purchased some cells from various vendors such as MEC and battlepacks.con.
My understanding is that cells are in short supply and some vendors are out of stock and ill be for some time. Last check battlepacks still had a good supply.


Charles

< Message edited by everydayflyer -- 6/23/2008 8:43:52 PM >

(in reply to dirtybird)
       Post #: 8

RE: Dead 4600mah A123 pack after 4 charges? - 6/23/2008 7:26:09 PM   
everydayflyer



Posts: 932
Joined: 8/21/2005
From: Buchanan, GA, USA
Status: offline
quote:

If you charge one to more than 4.2 volts you will ruin it. It will get hot and after that it will be shorted.


This may be your experience however mine is very different.

I charged a 4S at 5S settings to 18.125 volts (4.532 volts per cell) and it now has over 100 addtional flights on it and is fine.

A member on RC Groups cycled a single cell to 4.3 volts and zero volts 300 times and the cell was still good.

Charles

(in reply to everydayflyer)
       Post #: 9

RE: Dead 4600mah A123 pack after 4 charges? - 6/23/2008 8:26:08 PM   
dirtybird


 

Posts: 3031
Joined: 1/25/2002
From: Mesa, AZ, USA
Status: offline 		I am in Seattle and called MEC. He said the Korean factory had been on strike but is now back to work and he should be getting new cells this week.
Yesterday I found two cells at a local hobby shop at $20 each.
I installed a new one in a place that one of the cells had gone bad in an 8s1p pack and begin charging at 30 and 3A. 15 minutes later I noticed the new cell was smoking. Another cell had shorted out and the extra voltage was too much for the new cell. 30/7 = 4.5 volts/cell. I removed the voltage but it was too late. The cell vented and squirted brown stoff all over the place

(in reply to everydayflyer)
       Post #: 10

RE: Dead 4600mah A123 pack after 4 charges? - 6/23/2008 8:51:41 PM   
everydayflyer



Posts: 932
Joined: 8/21/2005
From: Buchanan, GA, USA
Status: offline 		Balancing taps / leads and at least monitoring each cells voltage would prevent this.

I know pete (MEC) ststes they do not need balancinag as do many others. my experience says some do need balancing and so do not. Some need balancing often and some never do . They are like LiPolys in this reguard. If you go to the ytrouble of cycling the cells, matching cells with same IR and capacity then they rarely ever need balancing. If you do not discharge more than 2000 mAh from them they rarely need balancing. If you slightly over charge the cells to 3.7 to 3.85 they rarely need balancing.

If you take 2-10 cells at random, build a pack ,fast charge fly it and never check balance then you may or may not get by with it. Balancing leads(pitailgs0 are cheap. it takes two extra minutes to solder a 6 lead 5Sone to a pack. It takes 5 sec. to connect to a balancer.


Charles

(in reply to dirtybird)
       Post #: 11

RE: Dead 4600mah A123 pack after 4 charges? - 6/24/2008 1:24:22 AM   
fb5b


 

Posts: 10
Joined: 6/23/2008
From: , AUSTRALIA
Status: offline 		Finally got a reply from these jokers, which was along the lines of send them back AT YOUR COST and we'll have a look then you pay us to post them back again AT YOUR COST.

Screw that!

Pulled the pack apart, 2 cells are at 3.3 volts one is at 0.3 and one is at 0

This is after charging on THEIR balancing charger.

I give up on these jokers. Lipo never gave me this issue!

No way in HELL would I recommend A123 racing to ANYONE!

(in reply to everydayflyer)
       Post #: 12

RE: Dead 4600mah A123 pack after 4 charges? - 6/24/2008 2:07:13 AM   
wasting money


 

Posts: 71
Joined: 8/26/2007
From: Springfield, OH, USA
Status: offline
quote:

ORIGINAL: fb5b

Finally got a reply from these jokers, which was along the lines of send them back AT YOUR COST and we'll have a look then you pay us to post them back again AT YOUR COST.

Screw that!

Pulled the pack apart, 2 cells are at 3.3 volts one is at 0.3 and one is at 0

This is after charging on THEIR balancing charger.

I give up on these jokers. Lipo never gave me this issue!

No way in HELL would I recommend A123 racing to ANYONE!

Sounds like A123 has some issues with their cells right now. I just got their charger and a 3s1p pack on Thursday, pack was charged maybe 5 times and I have a dead cell in my pack. Took the rubber end caps off the pack to measure voltage and found 2 had 3.4 and 1 had 0.0. I didn't order mine from A123 but from "hopmeup" on E-BAY. On the bright side, I found that I like 6.6 better than 9.9. Much more contollable, but still not happy about the dead cell.

(in reply to fb5b)
       Post #: 13

RE: Dead 4600mah A123 pack after 4 charges? - 6/24/2008 2:11:06 AM   
snellemin



Posts: 738
Joined: 3/22/2007
From: Tomball, TX, USA
Status: offline
quote:

ORIGINAL: wasting money
Sounds like A123 has some issues with their cells right now. I just got their charger and a 3s1p pack on Thursday, pack was charged maybe 5 times and I have a dead cell in my pack. Took the rubber end caps off the pack to measure voltage and found 2 had 3.4 and 1 had 0.0. I didn't order mine from A123 but from "hopmeup" on E-BAY. On the bright side, I found that I like 6.6 better than 9.9. Much more contollable, but still not happy about the dead cell.



I have bought from Hopmeup before and had the same thing happen to me with two 3s1p packs. I just made a balancing adapter for them and stuck the blinky balancer on them after i charged up the pack a bit. All my packs balance right, except the one I had overheated.

_____________________________

check out www.Hamdrl.org
Snelle-RC, A123 Racer

(in reply to wasting money)