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I'm definitely pro-EV. As soon as it's practical for us I'll get one. However, I do worry that there are so many dimensions to optimising EV batteries (degradat

I'm definitely pro-EV. As soon as it's practical for us I'll get one. However, I do worry that there are so many dimensions to optimising EV batteries (degradation, fast charge / discharge, stability, temperature tolerance, weight, cubic volume and price) that we might not be able to find anything that really changes the game. By which I mean a doubling of capacity, so 200kwh easily in a car, by my maths that's what we need to keep a light van (3.5t say) busy for a whole shift. Or in my case to tow a caravan 300 miles.

bryanlarsen 4y ago
The only thing preventing manufacturers from putting 200KWh in a full size van or truck is cost, and with battery cost reducing 90% per decade, that should not remain a barrier.
- pclmulqdq 4y ago
  The cost drops of the last decade will likely not continue going forward. It is more likely that lithium ion batteries will end up kind of like Nickel-based rechargable batteries: a huge spurt in cost reduction as they become mainstream, then not much after that. Lithium ion chemistries have a few more cost reductions to go, but not another 90%. Semiconductors spoiled us into thinking we could ride one technology idea down an exponential curve forever, but most technologies don't have that kind of progression. By the way, semiconductors didn't have that kind of progression either - chips from 10 years ago look very different than today's.
  - bryanlarsen 4y ago
    It's all about the experience curve. For every doubling in production, cost drops 10-25%. There are very few exceptions to this. Nickel battery production has decreased as they're being replaced with Lithium batteries so they're no longer riding the experience curve. Semiconductors have a relatively constant price per chip but a regularly decreasing price per transistor. We need about 1000TWh for the clean energy transition, half for cars and half for the electrical. There might be better substitutes for the electrical grid, but cars are going to use something that looks a lot like a lithium-ion battery, like sodium ion. So I figure we've got solid demand from our current 500GWh/year up until at least 32TWh/year or so, 6 doublings, which should lower the price by about 90%. Look at the other side. Tesla's battery day announcement in 2021 promises 56% cost reductions in 4 years via 6 enhancements: silicon anodes, cobalt-free cathodes, dry electrode process, structural batteries, tabless electrodes, larger cells. Only the dry electrode process is particularly innovative or risky, but the others still add considerable cost reductions. Not all of Tesla's innovations may pan out, but they're just one of many companies and Universities researching batteries, many of whom are more innovative than Tesla is.
    - pclmulqdq 4y ago
      I'm fully on board with you with Wright's law, but that's what we have some idea of demand for, but not what we can supply. Battery supply has a lot of constraints, and they will eventually lift, but not necessarily quickly. Also, Tesla has a very spotty track record on predicting its own innovations (yes, even on battery design), so I wouldn't take that prediction too seriously.
deleted 4y ago
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bryanlarsen 4y ago

The only thing preventing manufacturers from putting 200KWh in a full size van or truck is cost, and with battery cost reducing 90% per decade, that should not remain a barrier.

pclmulqdq 4y ago
The cost drops of the last decade will likely not continue going forward. It is more likely that lithium ion batteries will end up kind of like Nickel-based rechargable batteries: a huge spurt in cost reduction as they become mainstream, then not much after that. Lithium ion chemistries have a few more cost reductions to go, but not another 90%. Semiconductors spoiled us into thinking we could ride one technology idea down an exponential curve forever, but most technologies don't have that kind of progression. By the way, semiconductors didn't have that kind of progression either - chips from 10 years ago look very different than today's.
- bryanlarsen 4y ago
  It's all about the experience curve. For every doubling in production, cost drops 10-25%. There are very few exceptions to this. Nickel battery production has decreased as they're being replaced with Lithium batteries so they're no longer riding the experience curve. Semiconductors have a relatively constant price per chip but a regularly decreasing price per transistor. We need about 1000TWh for the clean energy transition, half for cars and half for the electrical. There might be better substitutes for the electrical grid, but cars are going to use something that looks a lot like a lithium-ion battery, like sodium ion. So I figure we've got solid demand from our current 500GWh/year up until at least 32TWh/year or so, 6 doublings, which should lower the price by about 90%. Look at the other side. Tesla's battery day announcement in 2021 promises 56% cost reductions in 4 years via 6 enhancements: silicon anodes, cobalt-free cathodes, dry electrode process, structural batteries, tabless electrodes, larger cells. Only the dry electrode process is particularly innovative or risky, but the others still add considerable cost reductions. Not all of Tesla's innovations may pan out, but they're just one of many companies and Universities researching batteries, many of whom are more innovative than Tesla is.
  - pclmulqdq 4y ago
    I'm fully on board with you with Wright's law, but that's what we have some idea of demand for, but not what we can supply. Battery supply has a lot of constraints, and they will eventually lift, but not necessarily quickly. Also, Tesla has a very spotty track record on predicting its own innovations (yes, even on battery design), so I wouldn't take that prediction too seriously.

deleted 4y ago

[deleted]