May I ask why the two of you (John, Cor) decided to use Leaf packs rather
than Volt packs?  The spinel chemistry used in Leaf batteries is known to be
inferior to the NMC chemistry which I think is used in Volt packs, and the
Volt packs have liquid temperature control to further improve longevity. On
the other hand, the Leaf modules seem to be much easier to work with if you
want to make a custom pack, say by combining the basic 2s2p modules in
parallel to make higher Ah modules, or to fit an existing battery box in a
conversion.

Then there are also Tesla S modules available which seem to be the best
chemistry for longevity and the highest energy density.  Some are concerned
with the safety of these higher energy density cells, but the Tesla packs
seem very well designed for safety with each cell fused on both anode and
cathode, and my understanding is you have access to the bms wires from each
module so can straight-forwardly connect a bms to them.

Just wondering what drove your decision.  I've toyed with the idea of using
one of the above in my conversion for a couple years now, but my LiFePO4
pack, though 7 years old, is still doing fine so I'm reticent to spend more
money on batteries, and I'd kind of like to see how long it lasts before
significant degradation.  I lean more toward Tesla modules since I could
double my pack size and have a bit LESS weight, and I think with proper care
in the implementation, packaging, and operation (bms) they would be safe.  

I also prefer liquid cooling since I think the end of life of my cells will
be caused by creeping up internal resistance, not capacity loss.  We get
fairly high temperatures here in July and August (~100F, sometimes above) so
the higher internal resistance will result in more pack heating and pack
temperatures exceeding the ~40C (104F) limit above which it seems that
greater deterioration occurs. I've exceeded that a few times, and expect it
will get more frequent as ir creeps up.

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