Hi all, new forum member here. My boss owns an e825 2002 gem and tasked me with converting it to lithium ion. After reading through the forum i realize batteries around 12v would be the conventional option, yet my boss found 3.7v cells ( adding up to 14.8v batteries) and wants me to see if they can work. Does anyone know if a gem can take such voltages in series? Any advice would be really appreciated.
There is much much more to using lithium batteries in a Gem than just connecting some cells in series for the right voltage.
It’s well that you asked first. Most do not.
3.7v cells are LFP and not well suited for traction batteries. IMO
Those who know use cells designed for the latest production electric vehicles.
That being said, one of your challenges in a 2002 is fitting battery in the front. Where the weight is needed.
Where are you located and what mileage is expected?
Use 250-300 wh/mile ballpark.
Thank you for replying. Were located in the Tri-state area and my boss says he is looking for 30- 40 mile range and wants speeds around 25 to 30 mph (I assume the wh/mile is around 300 but i’m not sure if i calculated it right.) Hes very stingy about price I even recommended to him leaf or volt cells but he said no. Thanks for your help.
Key phrases picked out that need clarification-
yet my boss found 3.7v cells
Did he already buy these? How many did he get?
He’s very stingy about price
This is generally not a good path to follow when buying batteries. Yes, cheap cells can be found all over the place. This usually leads to some tired Grade B product and disappointing performance, eventually leading to future disappointment and the need to buy something else and rebuilding again within a year.
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Hello, my boss hasn’t bought the batteries yet but wants to buy either 3.2v or 3.7v cells. Also he’s convinced the batteries and seller are pretty legitimate. Yet I completely agree about using cation around cheaper priced cells. Thanks for your help. Btw nice profile pic!
Hi all, I’m new to the forum.
2016 eM1400 Utility (not LSV).
I have to replace the battereis and want to switch over to a Lithium Pack. I’m partial to BigBattery lithium batteries, but open to suggestions. I’m fine with the stock 48V, not looking to do anything crazy. Hoping to keep as many stock parts as possible. Can I simply swap out the 8 - 6v AGM batteries for a 48v pack like this…Husky 2 48v 100ah battery
Any help would be appreciated.
Frank
3.7v cells are LFP
I know you know what your talking about, but aren’t LFP 3.2v?
Good idea to check the specs on any pre-made battery to make sure it can handle power requirements. Most LFP batteries (Like the one you linked) wont work unless they are at very high capacities because they cant handle as much current as NMC batteries.
Most Gems will have surge amp draws of 200-350a. The data sheet for the husky says 225a for five seconds and continuous current of 100a. That wouldn’t cut it and could shut down, or even damage the BMS.
Stich with something like the mighty mite sold here for less… that can candle the amperage and is made for this type of work.
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This is the 12s sdi battery that I put in a 2016 e2.
I got 60 miles actual range fron the 224ah 10kwh configuration.
It is a factory built Samsung Korea battery.
Includes 350a jk bms.
I don’t believe that it will ship ups with the optional aluminum enclosure.
Meaning the car will need a floor under the battery.
This is my last one.
$2000
Best to get a freight quote in any case. Ups destroys heavy boxes.
In that case, I will include battery box as shown.
Look closely, the feet line up with oem mounts. May need re-drilling, depending on oem battery it replaces.
Connect the two battery cables. No changes needed to charger or bmc, in most cases.
If car limps after 30 miles, I supply a range doubler shunt.
If buying a different high range battery, 30m plus, ask how they handle the “limp” problem.
A non issue for the eM1400. Pop the seats out no tools reqired and swing the brake mount out if the way and rip out the lecoch agms under the seat slide the sdi in.
Come on Dave ypu know that! I bought my treasured Emmy from you!