New GEM Owner - Converting To Lithium Batteries

That’s them. Don’t ask me why why call themselves CALIB in the US, just be glad you have a LOCAL source for batteries! Do your research online to find out what the current “haggle” price is. It’s was hovering around $1-1.25/Ah/cell, but who knows now.

Yep…everything is a bit dodgy…that is why my caution. But, sounds like you did it without too much difficulty. This local to me guy from the DIY Electric Car Forum could be a big help. He yanked the engine and tranny from a Geo Metro! Also, my roomie/tenant is a Prius and Honda Hybrid Battery Rebuilder…so, I should be able to get it done…just the more info the better. Thanks again.

brent,

starting a lithium upgrade this week , inspired by reading about yours . all the info you gave really helped me get started . I started a new thread not to take away from yours . hope your available for some q’s soon.

mike

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Thank you bgeery. I am looking for upgrading a 2009 E4, so your experience in very helpful.

Just finished my 72V 130ah Lifep04 Upgrade and it is awesome.

I still have to clean the install up a bit but will keep you posted.

When you will be done, it would be to much to give me approximate cost for upgrading my 2009 E4?

Once I get my setup complete I will be happy to share all the specifics.

Joe

Thank you.

Have many other converted to Lithium ???

Where is the best place to get the software to adjust the engine and speed limiters ?

I did mine , there is a thread on here about it . didn’t us lifepo like this thread , used Nissan leaf cells instead .

I recommend converting to lithium . it does require some electrical knowledge , but the benefits are great .

like many others here on the thread , always available to help.

Forklift Electronics

GEM Car T3 Owners

newgem , I see your in Sanibel . I’m in naples , your more then welcome to stop by and see/drive my lithium gem .

I will be dilated. My phone 239-395-1590, so if don’t, mind give me a call or leave your number and I call you.

Do you use bms?
What charger?

I was worried about 1c or 3c lipo4 cells supplying enough current.
I have been told the “volt” li-ion batteries can do 1200 amps.
And 1/2 the money.
60ah for my 48v car <$1k

the volt cell are great . the problem is they come in subassemblies of 24v & 48v . so you cant get the voltages right for a 72v gem .

BUT for a 48v setup , absolutely .

if memory serves me right the original cells are only 45ah and the new 2015 cells are 50ah .

but you can buy a 48v module for like $400 . so buy 2 and parallel them . your talking $ 800 for a 90ah pack ! its a no brainer .

they can easily handle the discharge rate , that’s not a problem .

for your other question . no I’m not using a bms . the leaf models are a perfect match voltage wise . I have the charger set to charge them to 4.12v per cell and shut off . then the controller shuts down @ 60v from the factory , so that’s 3.0v on the low side . also these type of cells have stayed perfectly balanced . checked today and after dozens and dozens of charges they are all within 1/100th of a volt! no bms necessary .

in fact they are so perfect for the gem , the factory charge gauge works perfect and I didn’t even have to recalibrate it.

p.s. I had lithium profiles add to my delta q . you maybe able to use your standard charger depending on what it is .

called your number , lady who answered didn’t know what I was talking about.

The 48 volt packs are cheap, but I’d like another cell.
Hybrid has 60ah 58.8v packs for $849

[quote=Inwo;27547]The 48 volt packs are cheap, but I’d like another cell.
Hybrid has 60ah 58.8v packs for $849[/quote]

the 60ah well be the leaf cells

what’s the high voltage and low voltage cutoff on your controller ?

[quote=kinghappy;27549]the 60ah well be the leaf cells

what’s the high voltage and low voltage cutoff on your controller ?[/quote]

20% high cutout. 57.6 in theory.

I get a peak of 62 volts after charging without problem.
In a pinch, I think I can fool the controller with .6 volt drop to “sense” pin.
Hybrid sells these as a 48v kit. I suspect it will work.

My 48v Tomberlin is a pig accelerating. 25mph but no torque. Drops to 12-15 on slight incline.
3.8kw motor
Can’t find any helpful info on the T3 controller.