Earlier on this thread I wrote this:
JejuSoul wrote:Even though the IONIQ EV and the Chevy Bolt both have LG Chem battery packs the pack structure and the actual cells seem to be quite different. (Note the word seem - it is very hard to get any accurate info about the battery pack from Hyundai)
The IONIQ EV has a battery pack by LG Chem.
It has 192 polymer pouch type cells laid out in a series string of 96 sets of 2 parallel cells.
The IONIQ EV battery pack is 31 kWh and weighs 271.8kg -> Gravimetric Energy Density = 114 Wh/kg
The Chevy Bolt also has a battery pack by LG Chem.
It has 288 polymer pouch type cells laid out in a series string of 96 sets of 3 parallel cells.
The 2017 Bolt battery pack is 60 kWh and weighs 435kg -> Gravimetric Energy Density = 138 Wh/kg
I now have to reconsider because it seems the Bolt has 60 kWh usable capacity not 60 kWh total capacity as I wrongly assumed.
Making a rough guess that the actual total capacity is 66kWh then
The 2017 Bolt battery pack is 66 kWh and weighs 435kg -> Gravimetric Energy Density ~ 150 Wh/kg
This makes the Bolt cells better than previously assumed. This value is for the pack. The Bolt EV has a liquid cooled pack, so it is heavier than a comparable air cooled pack. I assume now that the Bolt is using cells that have a roughly 50% better energy density than the Ioniq.
As I commented above next year the Ioniq EV will get a 50% increase in battery capacity. I assume they will fit into the same volume as the current battery pack. This makes sense when we see those better cells already exist, and are already in production. The puzzle is why did Hyundai use the inferior cell at all. Why not go straight to the new cell.