LiFePO4 lithium battery

Sorry see where there was a thread few years back. Has there been any updates on using delta charger and LiFePO4 batteries.

Has anyone tried the LiFePO4 lithium battery in there GEM yet? If so what did you do and is it working for you.
Thanks Ed

My feeling is that the LiFePO4 technology works very well BUT it requires a different battery management system (BMS) designed specifically to work with that technology. Generally I’ve seen LiFePO4 sell [U]with[/U] their own BMS typically in the $6000 to $8000 range - though that may have come down since I last looked.

As far as I know there is a lot to recommend the technology performance-wise (life of pack, less weight, improved range, etc). The drawback is obviously the initial cost. They’d need to come down by half to make it a practical solution IMO - at least for me. I can buy several FLA/GEL/AGM packs for the price of one LiFePO4. You’d need to ask yourself how long you intend to keep your GEM.


Thanks I had 2 of these before and range wasn’t enough.

Resurrecting a VERY OLD thread to ask a question about an affordable(ish) option for my 2002 e825 (e4)
found these: EG4 8-Cell Pack Lithium Cells | 25.6V 100AH - Signature Solar They seem solidly built, are a great price, and i have to break up a pack anyway to fit into the three sections in my 2002 anyway. So three of these might be a good fit.

Questions… what BMS would you recommend for the 24s LiFePo4, and what setting for the Delta Qui-Q Charger if i go this route?

Hey man, long time no see/post…

for the love of god, please no, just no on the pre-package lfp cells.

Dave @Inwo has been working on a better solution for the 00-04 cars. We’ve been talking about it for a while now and it’s shaping up really nicely. Some field work currently going on by @AssyRequired and I did some minor work with the original test fitting on the empty boxes:

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Yeah, I’ve seen that. These aren’t really pre-packaged, just pre-assembled into a 24v pack . Three would be ~80v. I like the LiFePo4 chemistry because they are pretty safe and resilient and have a crazy long life span.

I like the front stack you guys are putting together. What will they run price-wise. My Dekka’s are still hanging in there after 7 years… but are starting to show their age. Want to weigh my options for when they decide to let go.

@inwo will have to answer the exact pricing question, but I don’t think it’s much more than what you would be looking at for the lfps.

You will almost certainly run into problems with two of those LFP packs up front and one in back because the BMS balance sensors are really sensitive to resistances and once you get into these long wires it becomes a nightmare as the resistance and line loss skyrockets. You really should put them all together.

Oh, wait, you’re in Modesto, right? George will be in Oakville in like 3 days and I think he might have some extra Samsung SDI 94Ah Li-Ion cells on his rig. 21 of them and you don’t have to change the charger, Dave was saying there might be a discount on these since they’re already on the truck.


The completed drop-in ready battery is $2750. Much less for parts to DIY.
I do have one onboard depending on @AssyRequired promise to a neighbor.

Modesto is almost 3hrs from here. I’m right between Fresno and Bakersfield (Porterville) not quite ready at the moment, probably waiting for the Dekkas to conk out. But I thought the LFP looked like a cheaper option (like @Inwo green cells of old, but more capacity) also would put them all under the seat together like the old green cells as well. Not set on anything yet, I was looking at off grid solar pages (for my RV) and saw those cells and thought I, or someone else, could have a simpler DIY system.

Up front looks good for traction and prevents the longer cable runs. But 3k, while I know it’s a deal, makes me cringe a little because I was lucky and gat the GEM in great shape for $3000 originally. I’ll get over it when it stops running and needs new batteries though.

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Poking around the link YB provided I am excited to see something that might have promise for the future.

Right smack in the mid of the EG4 Rack mounted battery are a couple of comm ports(CAN and RS485). Depending on what these are used for it might solve several issues (but also create another level of complex install?)

There is also free software on this page for monitoring the Batts. Whatever BMS they are using might be worth looking into.

They are BMS monitoring communication (For Growatt inverters, but not sure how specific they are to THEM) The BMS is inside and does it’s thing independently, but if you link several it will allow you to see combined info and monitor that from the inverter.

The Will Prowse Solar youtube channel shows him opening these up and talking about the BMS somewhere… I believe he even says which one it is at some point.

Found one: Quick Teardown: Server Rack 5.12kWh EG4 LiFePO4 Solar Battery - YouTube

And Another: EG4-LL 48v 100ah Battery Basic Teardown! - YouTube

Yeah, Monitoring is one thing and is more/less what I guessed. But there are two more RJ-45’s to the right to just look at individual cell V.

Having the ability to control or even have the BMS talk to each other would solve alot of problems. I’ve been waiting for something like that to happen.

You’ve been waiting for something new .
You’ve been waiting for a BMS like that come into your life.
You’ve been waiting for something make your batteries feel alright…

(Sorry. On hold with a vendor, goddamn Foreigner 4 album is their hold music. About to jam my rotohammer in my ear and pull the trigger)

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Be sure to mention that these are only suitable for standby or solar storage. 100 amp isn’t going to cut it for ev use.