Now that you can buy Leaf Battery packs from a 3rd party....

[GregH]

Can you get the code for a volt? Prius? Golf? Mustang? M5? C300?

I have the code for the Prius.. reverse engineered it myself at EnergyCS when we did the first lithium ion plug in Prius. NiMH battery and Toyota BMS completely removed and replaced with our own designed battery and custom BMS to spoof the Toyota Hybrid system. I believe we even have a patent on it (for all it's worth). My point being that reverse engineering enough of the CAN bus traffic to fool the Leaf into thinking it has a Nissan spec battery installed is not all that hard.
But then why go through all the trouble? I'd think an aftermarket module x 48 plopped into the existing battery box and Nissan BMS would be easier..
[edit] Didn't mean to imply in any way that Nissan would or should help facilitate such an endeavor.. just that it is possible.

 

[fotajoye]

Can you get the code for a volt? Prius? Golf? Mustang? M5? C300?

I have the code for the Prius.. reverse engineered it myself at EnergyCS when we did the first lithium ion plug in Prius. NiMH battery and Toyota BMS completely removed and replaced with our own designed battery and custom BMS to spoof the Toyota Hybrid system. I believe we even have a patent on it (for all it's worth). My point being that reverse engineering enough of the CAN bus traffic to fool the Leaf into thinking it has a Nissan spec battery installed is not all that hard.
But then why go through all the trouble? I'd think an aftermarket module x 48 plopped into the existing battery box and Nissan BMS would be easier..
[edit] Didn't mean to imply in any way that Nissan would or should help facilitate such an endeavor.. just that it is possible.

Thanks for the info: Yes, the idea is just as you reasoned; except replace the old modules with lower-cost, higher-density cells when they become available(not necessarily Nissan). And of course, one needs the codes to spoof the car if the cells differ.

You might find this interesting:

https://www.youtube.com/watch?v=PEHs3X75IDo&list=PL9E25D4D67516040F" onclick="window.open(this.href);return false;

 

[GregH]

I'm not sure if I'm actually impressed by the Argonne youtube vid linked above.. 5.5.5.??? Seems pretty pie in the sky to me... A couple of theoreticians adding up numbers and getting funding to pursue something others have been seriously working on for decades. Or maybe I'm just jaded in my old age and should be open to the possibility of radical breakthroughs :/

On the software side it would be interesting to slap 80-120Ah modules into an existing Leaf battery box with standard Leaf LBC and see how it reacts. I know folks with the equipment to make Leaf shaped modules out of 18650s that would have such a capacity.. but we calculated the impedance would be too high so the lack of TMS would kill it quickly. That would be a lot of $$$ wasted for a super pack that wouldn't survive long... sadly.

My guess is the capacity would still peg at 67.362Ah and charge up to 284 Gids (charging to 4.12V) but on the low side the 18650s we've used have a much more gradual drop off down around 3.6 to 3.3V unlike the Leaf cells that collapse below 3.6V. Most likely the Leaf would act normal then get another 40 miles down below VLBW with the GOM flashing "---" the whole way.. but you wouldn't actually turtle for many miles until the low cell voltage is reached.

 

[DaveEV]

I know folks with the equipment to make Leaf shaped modules out of 18650s that would have such a capacity.. but we calculated the impedance would be too high so the lack of TMS would kill it quickly. That would be a lot of $$$ wasted for a super pack that wouldn't survive long... sadly.

Another 20-30 Ah would be nice - surely someone makes 18650 cells with low impedance and more capacity than the LEAF? I have to imagine that Tesla's cells do OK since they pull similar C-rates from their pack, though they do use TMS. A ~40 kWh pack would only see 2C in a LEAF and then only for brief periods of time. The 60 kWh S pack sees up to 3.75C and the 85 kWh S pack sees up to 3.65C, cut the max C rate in half and it might be OK. I guess high speed freeway driving may be an issue...

It still seems like the easiest way to add capacity to the LEAF is an Enginer style add-on. With a proper BMS and a good quality 10 kW DC-DC inverter it seems like it could be made reliable. Have the DC-DC converter charge the add-on pack when the car is charging and then you don't even need an external charger for the aux-pack. Operation of the DC-DC converter is simple - discharge the AUX pack when the main pack is under a certain voltage and charge the AUX pack when the car is charging. I bet it could be made just about plug-and play if someone really wanted to without even cutting into the stock wiring harness. Drop in 8 kWh of reclaimed LEAF modules (12 of them), bolt them down in the trunk or under the trunk in the spare-tire space.

 

[GregH]

True.. but then you've added more weight and removed a chunk of your cargo area.. not to mention possibly placing batteries in the crumple zone of the vehicle. I felt the same way about our EnergyCS/EDrive approach to converting the Prius as compared to Hymotion and many others who offered PHEV kits. Ours completely replaced the existing battery and didn't extend more than a few more inches into the rear of the car (well EDrive, at least.. the EnergyCS/Valence pack did go back pretty far). Most of the other PHEV kits added a 2nd battery to the existing Prius NiMH hybrid battery... consistently overcharging the hybrid battery to convince the car to use more electricity. This tended to add a lot of stress to the hybrid battery and remove much of the regen capability not to mention adding a bunch of weight etc. On the Leaf you could be much smarter about it and inject energy only at lower SOCs, but I still don't think it's an optimal approach.