I put 6 Smart Batteries in my 2015 GEM. Since then my mileage has been around 22 per charge. The GEM just, suddenly, quits without warning. After a few minutes, and turning the master switch off and then on the power is restored, but cannot go but a 100 yards or so before quitting again. Each battery is showing 12.5 or higher and across the pack is 77 or higher. In my 2010 Gem I could get nearly 70 miles with these batteries. It has a stock Delta Q that will charge the pack to about 80.5. Cannot figure the quitting out since after each event I am testing to near a full charge and no error codes. Any Ideas?

I believe they use 6s liFePo wich should be charged to 94 to be full.
It may not balance properly only half charging them.
If any one cell goes low, bms will turn off.
Do you have access to cells?
Do they have a cell monitor communication to look at?
I would full charge it multiple times to get it balanced, before deciding one is bad.
It’s near impossible to know state of charge from the voltage. You may not even be charging half way.
Measure the time it takes to charge them. DQ is 12a if full power mode.
A 120 ah battery will take over 10hrs. More like 14 from dead to full.
A 60 ah over 5hrs.

Thanks for the reply. The GEM will not run at over 82 volts across the pack. Did not have a problem with these in my 2005 Gem. They are sealed in a pack with a BMS built into each battery. When I bought another charger for it that will charge to a higher voltage the seller sent me a wire that could be used to by pass the GEMs 82 volt limit, but I do not know what to do with it.

I’m only guessing.
The wire connects to pin 1 in the controller.
Even without it, I would fully charge the pack once in a while.
Without access to the cells, I don’t know what else to tell you.
The event that stops the gem may be to quick to see without a data logger.
Check connections for heat after a hard run. It could be that simple.

Pin one and what? As I said in the first post this problem never showed up in my 2010 GEM.

I found the name Barbara J. Bissen from Hokah, MN on the box that the charger came in. Does anyone know how to get in touch with them.

Easy enough. :slight_smile:
I’m the only one that makes them.
Pin one of the 23 pin connector on controller. Remove the pin. Put in the new one.
Plug the wire that was removed into the new wire.
Is there a number on the wire I sent you? “10” or such.


I have been off for a few days. If I found the right wire, it is about 25" long with pins on each end. I never did use the charger I bought from you. Any idea how I can sell it? Jesse

Can I get a new wire?

You were so correct. The batteries were not being charged to a high enough voltage to balance them. Charged and discharged them several times and now I can go 50 plus miles on a charge. I do not know how much further I could have gone but that is plenty for my use. When I quit I had about 77.5 volts across the pack and each battery was at 12.6 or higher.

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Are they 100ah batteries.
Thats ~ 8kwh. About the same as grant. I don’t think he can do 50M, but then he’s a hotrodder.

Yes, they are 100 ah Smart batteries with each having it’s own BMS built in.

The only, unexplained wire I can find around here is about 25 in long and has a pin on each end. No other markings. When I buy the new charger can I get a couple of the wires to defeat the Gem lockout?

How much voltage increase do you need?
Pm your address or include a note with payment.
If you send a dollar for goods and services, I can print a label from paypal.:wink:

If the wire has a bulge in the middle that’s it.
Replace pin #1 With that wire. That’s all there is to it.

I am going to run at at between 86 to maybe 90. No bulge in the middle of the wire I found so I will need two since I am playing with two Gems.

Payment on the way for one charger and two wires.


Thank you.

I will have to make them custom voltage. Normal limit is about 85v. I will raise it to 90.

My idea was to give you one with charger.

Is it ok to pay for the second one?

They are $25.



Just send one wire. I will get the other one later.


Don’t worry about it.
I made two, and knew you were in a hurry, so I sent them both. :smiley: