[quote=Inwo;27708]Someone on here did a conversion with more cells/ higher voltage.
I’ll look. I believe the 72v controllers can also do 80v.[/quote]
volt and leaf modules are fully charged @4.2v each .so 20 cells would be 84v. t4 controller can take up to 86v high side and shuts off on 60v low side.
Didn’t find exact thread. One lithium conversion thread linked to this.
25 cell.
different kind of lithium . those are the chinese made LiFepo4 chemistry . the chemistry Nissan, chevy, tesla and I believe all other manufactures use are the LiMn , (Lithium manganese ) .
LiMn batteries have higher voltages = 4.2v
LiFe4 have =3.65v
you need 20 leaf cells for a gem, weight =80 lbs
you need 23 Lifepo4 cells (60ah) = 125lbs
you can do it either way, but after all the research I did , I went with the leaf cells . they are made for the specific application of ev’s.
hope this helps
and store more power per pound then LiFepo4 batteries .
I understand the different voltage per cell.
What getting at, is if a higher voltage will work.
My example was 25c X 3.65 = 91.25v
Hybrid has a24c pack 24 X . = 100.8v, yet they call it 88v.
I’ll research. It may be different chemistry.
ps.
I’m not questioning your info. I’m just looking at options.
Here’s the info.
Too much voltage?
its just like your regular batteries , they have a nominal voltage of 12v but fully charged a gel is about 12.9v . so the leaf/volt cells have a nominal voltage of 3.7v so 24 = what he shows 88v. but when you charge them they go 4.1v to 4.2v so now you have like 100v . too high for you controller. if you try and undercharge them so your controller well work you wont have any range .
I did a calc to see if I could add an extra cell to mine . because of the under charging I would have had slightly less range with the extra cell.
It looks like 96v is max allowed. I’ll find out if it’s more when controller is programmed for 80v.
I have a feeling, no.
mine error at 86v wonder if different controllers are different ?
That’s good to know. Other info may be for the 80V controller.
lithium packs are now available . I started another thread for this . these are twins to the one I use . Nissan rates these cells at 80% capacity after 5 years with 12,000miles a year . and 70% capacity after 10 years based on 12,000 miles a year .
the packs only weigh 85lbs compared to 425lbs for gel batteries . your cart well be faster , handle better . climb hills faster , last much longer and you can use the full capacity of your pack every time without worry of destroying it .
it comes in a assembled pack that is ready to drop in.
mike
update: gwest is now selling these as complete packages . he has done coversions on late models as well as early models . Grant is great to work with.
update:
it has been about 1.5 years since I have done this conversion . still works great . cell range is about the same and all cells have stayed in balance without using a bms .
a few people have now done these and all reports have been good with no reported problems . gwest has a thread on here showing the performance before and after , worth checking out . stock motor has been loving the higher voltage and showing no signs of problems . someone can do this and add one of Dave’s MM and you would have an awesome cart .
fyi a stock gem with just a lithium upgrade well outperform a gem with an r4f aftermarket motor and controller upgrade. not to mention longer range.
I well update this thread as time goes .
Mike,
Thanks for the update. I’m new here and hadn’t run across the thread until you posted today’s update.
Having just read through the entire thread I see that some of your picture links are no longer working, as well as some of the photo’s containing yoga pants instead of batteries.
Please re-post photos of this project when you get a chance. I’d love to see the finished product.
Are you still making these kits?
If so, are the prices the same?
Thanks
Dino
there is a turnkey GEM battery kit but it costs more than that…KING HAPPY, CAN WE SEE PICS PLEASE?
Thanks,
Jeffrey
See Grant’s on page 10.
http://www.electricforum.com/cars/gem-nevs-forum/9983-lithium-conversion-10.html
pictures are on page 2 . the last picture is the pack sitting between the frame rails under back seat . is there any other pictures you need ?
Realize this is a super old thread…but fascinating nevertheless. @LithiumGods you still making these packs or can you point me in the right direction.
Inwo is your guy . He has supplied many on here with lithium packs . Let me know if i can help
Hello Kinghappy, I am looking to build some golf cart packs using Nissan Lithium Gen3 batterys. I will be putting 3 modules together to create a 48v system. Can you tell me where I can get the orange (color really does not matter) frame that sits on top of the contact posts?
Any info on where to buy those and other components would be greatly appreciated
Thanks
Villageway
got them from hybrid auto center in Las vegas , they make them
