[BeeOnRope]

> While the scalability behind silicon was perhaps easier and faster, there are similar effects at work for batteries ... The thinner the layers, the higher the capacity as you have a smaller distance between positive and negative layers.

I'm arguing it's not at all all similar. The capacity of a lithium ion battery is fundamentally limited by the amount cathode material it contains, along with sufficient electrolyte to support it, just like any other battery. Making other materials thinner, allows you to stuff in more of this stuff, and other changes in the arrangement may make the process more efficient, but up to a limit. There is hard cap to usefulness of all of these processes, at the "theoretical efficiency" and in principle softer caps before that point long before you approach the theoretical caps.

If you have a chance, ask the battery chemists you know what the best-case storage is for a particular chemistry and cathode material, compared to what is available today. I don't think it is more than 10x aware and is probably much less.

That's very different than CPU scaling where you started out many billions of times away from the physical limits of the computational capacity of the material, and many trillions away from the theoretical physical limits of computation.

So no, thinner stuff isn't going to sustain a 15% annual increase in efficiency [1]. In fact, I don't think think it will even sustain a single 15% increase from today until the end of time.

Of course, there are many other vectors along which battery efficiency can increase when the denominator is "cost", even if the storage/size doesn't increase much. You can increase manufacturing efficiency. You can introduce new form factors. You can tweak the chemistry. You can carefully match the required discharge characteristics to the application. Outside of the battery itself, you can improve charging and discharging algorithms, you can use finer-grained control over smaller groups of batteries, you can improve thermal management. However, these are just in the range of normal industrial optimizations that apply to any product. You can replace "batteries" with "lettuce" in the above and come with a similar list.

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[1] To be clear, there is no 15% increase in battery efficiency per year, when measured by volume, weight or other physical characteristics: that stat must involve "price". Panasonic, the best and biggest Li-on player out there, has barely budged in efficiency on their headline battery, the 18650.

[marshray]

> ask the battery chemists you know what the best-case storage is for a particular chemistry and cathode material

It's entirely possible that with an exponential increase in production volume (i.e., funding) we could see some new chemistries appear.

Compare to Silicon Carbide (blue LEDs) and Gallium Nitride (power transistors).

[BeeOnRope]

It is possible. In fact, I definitely expect to see new chemistries and anode/cathode materials appear.

The question is how much it will buy us.

Unlike other domains where theories or algorithms or medicines or whatever appear almost "out of thin air", the periodic table is limited and the mechanism of battery operation is well understood, so I think there is already a pretty good grasp on the possible materials that can be used, even in theory.

For example, Lithium is used for a reason, something like it's electron carrying capacity per unit weight. There are no other elements waiting to be discovered that are going to be better. Cathode materials are more complicated, but I don't think there is any order of magnitude improvement hidden out there.

I could certainly be wrong.