Tesla to gem battery upgrade

I have a fleet of 10 gems hauling people around. They all range in years from 2012 to 2014 and have gel batteries. I recently came across used Tesla batteries and wanted to see if any one had tried this or knows if this would work.

Then if it does will the stock charger work. Are their user upgrade kits available?

Dave, @Inwo , is your man.

You will need 20s to 22s for good performance. 23s or 24s for hotrod. Charger can be programmed for lithium.
@MikeKC is finishing a Tesla3 25s upgrade in 2016 model.

Yes, Yes I am, Should be in place this week !! 100v/240ah.
8kw AC Motor upgrade
Sevcon Size 6 Controller upgrade

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@MikeKC I’m so jealous. Where’s that thing going? Between the frame rails? When @Inwo mentioned the 6’ tesla pack that’s the only place i could think of. are there cross braces there? you gonna put some sort of protective pan under it?

So…Long story.
This battery was going to be installed on an 08’ E4 and yes it will fit between the frame rails. EBrake cables might need shifted just a little but other than that it should fit right in, the cross members are not in the way. If you put it all the way to the back, the front will but just under the frame to front end split. Actually works out pretty nice. The battery is encased in hard plastic and well protected but yes it would be best to cover it with a least a thin sheet of aluminum or plastic pan.
But… Then I got this16’ and my plans changed.
Now I am going to slide it in on the floor board, the 16’ and newer are wide open all through the middle, the battery is only 3" tall so it will not inhibit the passengers hardly at all. Remember the old drive shaft tunnels in the old day cars, it will be kinda like that but only 3" tall. The front will stop almost flush with the front seat brackets so the driver and passenger will not even know it is there. Again, I think I will build a cover out of black star board or something just to protect the battery from kids climbing in and out all the time.
I also have one of these batteries that we are putting in a E6, the cross members ARE in the way on this car, we thought it would be the same as an E4, but it is not. Have not figured that one out yet.

@MikeKC funny that i never realized that the late models had such an open area under the seats. I went back and looked at some pictures and was surprised.


For the e6 2014. I found these modules:

Voltage nominal: 3.8V/Cell, 22.8V/Module
Charge voltage cut-off: 4.2V/Cell, 25.2V/Module
Discharging cut-off: 3.3V/Cell, 19.8/Module
**Maximum Discharging Current (10 sec.):**750 Amps

Do you think 3 of these would work for the 2014 e6?

Will I still be able to use the original dash board?


You do not list the Amp Hours for these modules, that will be a major consideration.
As for the voltages you can use the stock controller up to about 85ish volts so you will actually be a little low on voltage a full charge. You would be at 75v and with a new DQ Lithium charger you can only go down to about 70v before it will not engage to charge, the GEM is dead at 65v.
You need to find cells that will get you in the ~83-85 volt range at Max charge with about ~120 - 150Ah, maybe in an E6 even more if you want to keep everything but the charger stock and not run a hotrod setup.
I put four BMW i3 packs in a buddies E6, runs 98v and has great range. (it’s at about 140Ah). He can still use the stock controller and dash due to @Inwo great spoof. So a search on that.

So basically the tesla batteries voltage just doesn’t match up to what I need, damn.It was listed as 250 Ah which would have given me great range.

I just can’t stand the gel batteries anymore and need to upgrade to something that will give me the range I need. $3000 to replace the gel batteries sucks! I rather buy something that gives me more use.

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so I have had experience in the past where the car would give an error code for over voltage. if I use 2 45v i3 packs, that puts me at 90 volts. Your buddies car didn’t freak out with such a high voltage?

Oh, these are Tesla batteries, you are correct, those are the older modules with 18650 cells in them 25volts per module. I am using the new Model 3 modules, these come in two sizes, 23S (85 -90v) and 25S ( 90 - 116v). I am using a 25s. If you could find a 23s ( @Inwo) it would be perfect for you. 240Ah at 85 - 86 volts. You would have a 50 mile car.
You could probably do all that including a new charger for less than new GEL’s. - besides the fab work to mount the battery.

High Voltage cars are becoming pretty common, you can make the car happy with just a few changes and run up to about 99v.
Two of those packs would give you about 60Ah, probably a 6 to 8 mile car with the size of an E6. They are great batteries tho.

Yes! this is what I am looking for. But I am guessing this won’t be cheap unfortunately.

I think you two (@Inwo) need to just go into business as a gem upgrade company. I bet there are people who are less inclined that would send you their cars.

The search begins !!!

@Inwo has what you are looking for - PM him, I bet he can get you into the price you are looking for, shipping will be your biggest hurdle. Don’t know where you are, he is in MN.

I will be driving up to see him soon from Kansas City if that is any closer to you.
Motors - Controllers - Batteries all coming back to KC.

Where are you located? Near any members?
I can source the parts and advise, but not interested in expanding my business.
@grantwest Ca. @LithiumGods Florida. @MikeKC middle.
They are willing to do the work, rather than just talk about it, like myself. :slight_smile:

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I’m in New Jersey. So not to close to anyone, unfortunately.

Well, on a good note. There are probably alot of wrecked Model 3 in Jersey, should be able to find a battery module.

Tesla3 batteries are pretty common, but high voltage.
Also a pain to connect balance leads, until a solution is found.

That’s it, I’m out… LOL :slight_smile: