Yesterday I decided to ride the converted Vectrix (50 AH Li-ion) until the batteries were dead - since I haven't done that in a long time. But, I didn't plan my ride very well and ran out of juice a few miles from home. I "pushed" the bike by walking next to it while it was still running - the batteries continued to push the bike along at 1 MPH for a while. During the last few blocks I turned the key off and just pushed it.
When I got home and plugged it in it wouldn't charge! The red warning light was on and the alarm sound was screeching. Terrified that I had damaged the batteries I tried again, this time pressing and holding the reset button (from Antiscab's conversion kit). The charging started, but would only trickle charge at 1.7 Amps. After a few minutes it stopped charging. I unplugged it, plugged it back in, again using the reset button (I finally just shorted across the terminals so I wouldn't have to hold it in place). Again it started slowly charging. I had to do this several times, but finally the red light turned off, the high-pitched alarm sound stopped, and it started charging at the normal 9.5 Amps.
This morning the battery pack was fully charged and everything appears back to normal. Whew!
I now have 14,000 miles on the bike and this was the first time I ever had to push it - but it was my own fault. Thanks to Antiscab's kit I was able to revive the dead batteries!
Oh boy, those are NOT the original NiMH batteries, but rather 50Ah LiFePO4? I would most highly recommend that you never, ever, even contemplate to ride your pack down so low again!!! Your precious cells will die on you, and they may have already been severely damaged by this single deep discharge. In the first place, why were you doing it? As far as I understand that bar-stuff does not work properly anyway after such a conversion, so why on earth are you intent on driving your Li battery pack to it's wits' end???
Don't do it, if ever you can help it! The two things Li cells do NOT like: Overcharge and over-discharge. Anything in between they hardly care about, but at the ends of their envelope they suffer gravely and irreversibly.
My rides:
2017 Zero S ZF6.5 11kW, erider Thunder 5kW
Even the good A123 cells are simple to damage. Discharge them only below 2 Volts.
Or better discharge the pack until the first weak cell changes polarity.
They will than still work but with reduced capacity.
If you want to burn your money you should go on in this way.
People get confused by battery technologies, and the manufacturers sometimes make it worse. The owner's manual for my SLA EZIP bicycle, for example, tells you to run the battery pack through three complete discharge/charge cycles to 'condition" it. That's right: they tell you to try to kill or least hurt your battery pack while it's still brand new. I know this isn't the case here, but lithium packs do get marketed as being capable of much deeper discharges than lead or NiMH chemistries. Now that it's become clear that this really isn't true if you want to preserve the packs, the word needs to get out - as simply and clearly as possible - just how to treat each specific kind of battery...
Don't run a Li-Ion or LiFePO4 battery flat. You will damage the weakest cells in the pack. The same applies to a Vectrix with the original NiMH pack. The weakest cells will be reverse polarised and dammaged. Some people like to do this because it resets the battery gauge but it is the only way that I know of for an owner to ruin their battery.
Ha! No worries everyone - I didn't explain well, obviously.
My plan wasn't to run the batteries down to the point of being damaged... can I hear a "duh"? ;-)
I typically only burn a few Amp-hours before recharging as I have a short commute, but decided last weekend to go for a longer ride - near the capacity of the battery pack. My mistake was not calculating the correct distance I could ride based on the remaining battery charge.
Antiscab's BMS and the Cycle Analyst warned me well before I could have done any permanent damage. I got off the bike and pushed it home, rather than stressing the batteries below the 116-118V threshold.
My point of the post was that Antiscab's conversion kit made it possible to initiate a slow recharge. Without it I would have had to get an off board charger to accomplish the same thing.
The bike is running and charging just fine - the thing continues to amaze me.
Ride on!
Why does the charger not start if the voltage was above 116V?
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There is always a way if there is no other way!