I think i'm gonna puke.....or cry... maybe both..

Ypedal

Ypedal

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Dec 27, 2006
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Moncton NB, Canada
Awsome sunny 18 celcius out there today, amazing weather, i decide to top off the chopper for a ride...... get the lightbulb rack to drain a bit and then re-fill them, put the CA on the 24 cell PSI pack and no life to the CA..... :shock:
'

Get my volt meter, check voltage, 0.150 mv

:shock: :shock: :shock:

Somehow, the Soneil chargers, being connected to the pack for 3 weeks, have managed to drain it completely. :evil:

There goes 1000$ :|
 
Ouch! :? If they are PSIs, they might be recoverable. Try slow charging them, at like .5A, but watch for heat. If they are truly toast, they'll get hot as soon as you connect a charger.

--Gary
 
Anything that connects to the battery needs to have a circuit built in that physically disconnects itself once done charging. That or something that will periodically retest the battery charge to evaluate if it should start charging again. We need to start demanding this from the manufacturers.
 
Soneil chargers, as far as i knew, would not drain a pack if connected but not powered up...

That was it.. no BMS nothing.. the DC/DC converter was plugged in but not on and main contactor was open circuit so the controller was not a drain.. It has to be the soneils.

got 1.2 ah back in so far.. I had to series up 20 konion cells, in series with one of my array of 6x 200w lightbulbs to limit current and zapped the pack in 2 second bursts at a time until the Soneils kicked in..

All cells so far between 3.150v and 3.290v ... no heat from the cells yet.
 
Aiiieeee, what a scare for you. I guess only a load test will tell what damage you have done?
I just ran out to the shop in a panic, as I have not touched the scoot in 2 weeks and was sure I left the charger plugged in to it and not the wall. Good surprise, it was not plugged in either end.
Great of you to post for ALL! :shock: :shock: :shock: :mrgreen:

Edit; Now I read the posts again, I'll go out and throw the breaker too. Even though my controller does not appear to draw power unless the key switch is on.

E2..Chinese piece of bat dung; You can get your finger in the little hole to flip the breaker off, but you need a hook to get in and turn it back on. BIGGER HOLE coming up.
 
I've revived 2 headways, they sagged like old boobs afterwards and now are floor dragger paperweights. Hope yours are still round and firm. :lol:
 
My "dead" Fatpacks are back to life after going down to 2 volts. Maybe there is hope, Y!
otherDoc
 
I figured they'd be okay. These PSI cells are pretty resilient, especially if they don't get discharged at a high rate. If you were running them in on your bike, and ran them down without an LVC, they can and will reverse, and then you're f'd. Draining them down at a trickle rate won't kill them. They may not be damaged at all, and probably still have their full capacity. Great cells, for sure. :)

-- Gary
 
wow, there is still life in these cells. Freaking amazing.. a testament to PSI i suppose!!
 
As long as they discharged slowly enough that none of the cells got reversed they should recover OK. I'm not sure what this does to the long term life (probably not good), but I've been surprised at the ones I tested that were zero volts for a couple of years and seemed to fully recover (Li-Co laptop cells).

A diode in series with the charger will prevent drain, but the diode will get pretty hot at higher current levels. It will also introduce a little voltage drop, which would need to be compensated for.

Another trick would be to use a relay in series with the charger output that has a coil powered off the mains AC. As soon as the charger is unplugged, the relay opens.
 
Hoo boy! hope you still get cycles out of em at least till you are on to the newest nano whatever is next summers thing.

Goes to show, only one proper way to store a battery, even for a few weeks. Completely unplugged from everything. Kind of a pain to keep having to ride different bikes to keep the battery freshly cycled sometimes if you have more than one. Even in sunny NM.
 
I have powered Soneil 10A 36V charger connected to my 12 in series LifeBatt/BMI cells/with VMS boards/ for hours at the time long after the pack was charged.
It allows cells to be balanced, becuase VMS boards activate itself from time to time.
VMSs would never turn on for balancing if charger is disconnected.
One VMS board is connected to balancing leads of 4 cells, once voltage of one of cell goes above certain point VMS activate balancing
I don`t see the point to keep charger connected to cells once it is depowered.
MC
 
depending on whether there is 5k or 3k across the output cap, the drain at 85V would be about 1/2 to 2/3 Ah/day so 2-3 weeks for a 10Ah pack and it's discharged at that rate. of course as the voltage drops the current drops so double that for reality.

so 1-2 months for a 10Ah pack left on the charger. more like a month max since the cells hold their voltage for a long time.
 
Left my controller turned on, after a long ride, for four days a few weeks back. I was feeling kinda sick about the A123 pack too. Batts checked out at .8V each but the pack charged up fine and seems to be doing as well as before the abuse. I have really not been kind to my battery packs this year but have not seen any indication of reduced capacity as yet.

Hope things werq out well for you also.
 
A REALLY nice feature to add to the various DIY controller designs currently being masterfully debated here would be an auto-shutoff feature. If the system was left for more than a few minutes without throttle, it would shut down and go into a very low current standby mode (and/or scream bloody murder).
 
Ypedal said:
Just tested all 24 cells this morning, all 24 are showing 3.334v to 3.339v !!

Going out for a test ride now ! :D
Click to expand...

Did they work?
 
Ypedal,

These are Lifepo4, right? What's the C rating and size in Ah?

I think it's amazing that these cells were able to practically rise from the dead!

It would be nice to worry about over discharging batteries If batteries can consistently rebound like this.
 
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