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> Batteries are now being produced at a rate measured in TWH per year

I don't disagree with you, but I think specifically lithium batteries for storage is going to be a small part of the picture as we move towards having larger capacity. Sodium ion batteries in particular remove the resource bottlenecks that still hold back battery storage. That said, yearly additions to grid-scale battery storage (of any type) is basically doubling every year.

https://www.iea.org/data-and-statistics/charts/annual-grid-s...

https://www.iea.org/reports/batteries-and-secure-energy-tran...

To the point, that by some very basic projections I made, it looks like there will be more battery capacity than daily solar generation by 2034, and then more capacity than daily usage less than a year later.

https://www.desmos.com/calculator/lunahw7gvo

Especially for grid storage sodium ion is looking very promising. As are several other chemistries. But most of the current production is still lithium based for now and it will take time for that to change. I would say non lithium storage might become dominant from the mid 2030s and onward.

As for battery capacity. There will indeed be way more batteries than energy generation. But that's only a problem if you assume all those batteries are being cycled to capacity continuously. IMHO that's actually not the case. Most car batteries don't get drained on a daily basis. It's more like once a week or two weeks for average drivers. Same with grid batteries. They are used more intensively of course but also oversized so they don't constantly run out.

My point was that most batteries are, on average, holding a charge that's probably close to fully charged (or 80%, which is more optimal for some battery chemistries) and that only fraction of that aggregate capacity is discharged and recharged on a daily basis. Having that much batteries is really good news. IMHO it's a trend that will accelerate as batteries continue to get cheaper. We'll just buy more of them and find more places where it's nice to have them. Think of an e.g. AC units with a battery that can charge during the day and discharge in the evening.

As for the IEA, take their numbers with a grain of salt. They are notorious for having to correct their own predictions regularly. And there are some well known issues with their modeling and assumptions. Generally, you can subtract at least a few years from most of their predictions.

I'd recommend reading some of the reports by Bloomberg NEF they've had a few interesting reports on investments for battery production. Apparently we can look forward to over production and price drops next year already.

> But most of the current production is still lithium based for now and it will take time for that to change.

I wager differently. I see no reason why sodium-ion batteries couldn't leapfrog lithium, just based on simplicity and economy. I suspect the learning rate will be much quicker for sodium ion.

> Most car batteries don't get drained on a daily basis. It's more like once a week or two weeks for average drivers. Same with grid batteries.

That's only because grid batteries aren't really being used to offset peakers. They are basically arbitrage for when prices are very high, as lithium batteries can hold charge for a very long time and can be dispatched almost instantly. In terms of batteries being used in place of gas and coal stations, they will need to cycle deeper, but maybe after about 6-12 hours of capacity is reached, they won't have to.

That said, the graph I provided is global capacity. Right now, batteries are still a specialty item, but for broader applicability, they'll be needed in more diverse scenario, including where there could be large gaps in renewables output. But even anywhere, an emergency capacity of days would become necessary in order to divest fully from non-renewables as both baseload and peakers (e.g., when overcast, still, and very cold/hot temperatures, or powerlines failing etc.)

> As for the IEA, take their numbers with a grain of salt. [...] Generally, you can subtract at least a few years from most of their predictions.

My projections were based on historical data, and regressing exponential curves onto them. Not super scientific, but the exponential trends are very visible for solar, wind, and storage. The linear trend for energy consumption seems to be holding now for decades, but that could also change.

> Apparently we can look forward to over production and price drops next year already.

I've already seen the prices drop ~40% from August last year to January on prismatic LiFePo4. I bought twice as many cells for just a little extra. I expect to buy again next year and double my capacity for about the same as my first purchase. We'll see.

(adding some references to the points you made)

Government data show gasoline vehicles are up to 100x more prone to fires than EVs: https://electrek.co/2022/01/12/government-data-shows-gasolin...

Data from the National Transportation Safety Board showed that EVs were involved in approximately 25 fires for every 100,000 sold. Comparatively, approximately 1,530 gasoline-powered vehicles and 3,475 hybrid vehicles were involved in fires for every 100,000 sold: https://www.fairfaxcounty.gov/environment-energy-coordinatio...

Statistics from 2015 showed that 174,000 vehicle fires were reported, and almost all of them involved gasoline vehicles. Tesla claims that gasoline cars are 11x more likely to catch fire than a Tesla, and that the best comparison of safety is fires per billion miles driven. If we compare using this method, there are approximately five EV fires for every billion miles traveled, compared to 55 fires per billion miles traveled in gasoline cars: https://driveelectriccolorado.org/myth-buster-evs-fire/

From https://www.evlithium.com/Blog/advanced-safety-features-of-l...

Non-flammable electrolyte: LiFePO4 batteries use a non-flammable electrolyte that does not catch fire even if the battery is punctured or damaged. The electrolyte is a mixture of lithium salts and a solvent that is less volatile and less flammable than the organic electrolytes used in other types of lithium-ion batteries.

High safety: LiFePO4 batteries have a lower risk of overheating and catching fire due to their more stable cathode material and lower operating temperature. They also have built-in protection circuits that prevent overcharge, over-discharge, short-circuit, and physical damage.

That's an interesting set of stats, but it's not decisive. Some alternative explanations:

- The stats are just plain wrong, even at a surface-level inspection. They suggest that over 20yrs you'd have 3 fires for every 10 ICE vehicles ever sold. I ought to know 50 people in my current company who have had a car burn down, 30 in my last company, 5 in my extended family who I'm close with, 100 in a slightly wider net of acquaintances, .... I know 0. I highly doubt _anyone_ in the country comes close to having seen the "right" number of ICE fires, outside of firemen and people who otherwise gravitate toward such problems intentionally.

- The problem mostly isn't gasoline; it's shoddy manufacturing, especially wiring. How do the stats look if you ignore Hyundai and other particularly low quality manufacturers? Normalized by miles driven (which is closer to what ought to be correct), the delta is 10x rather than 100x. That's roughly the delta between how often a BMW breaks down vs a Toyota, so as a coarse estimate you might expect the data to be entirely explained by having the wrong denominator (cars vs miles) and the fact that you're just comparing different tiers of manufacturer.

- Back to the "denominator" issue, which is always a problem with normalized statistics. If your baseline isn't that each car has an equal chance to burn down for each mile driven, but that older cars are more likely to burn down because rust and other degredation allows for water infiltration and electrical fires, the older ICE fleet would naturally generate the reported stats.

- Back to the "denominator" issue, per car sold this year is maybe correct, per car ever sold is maybe correct, per currently running car over 20yo is maybe correct, per mile per one of the previous items is maybe correct, .... You really want to see the stats broken down by those categories, and to help avoid fishing for hypotheses to then come up with other testable ideas to examine for each interesting subcategory you find.

- It's always worth mentioning with EVs that the distributions aren't directly comparable. You have different populations driving the cars in different places from their ICE alternatives. Similarly to the previous point, you want to see results broken down at least by crude demographics. It matters more for self-driving safety claims, but it might be relevant here.

Elaborating slightly on the denominator and population issues:

The reason you care is that these stats aren't just abstract quantities; you're trying to gauge what the impact of a specific intervention might be. Suppose you could magically flip a switch and transition the country to EVs (which I'm not arguing against, just potentially the fire data thing), and you based that decision on this data. You weren't sold before, but since the fire risk is so low you were willing to apply that intervention. Instead of low fire rates, you might see:

1. When EV/EV collisions happen instead of EV/ICE, the higher total energy from heavier vehicles makes short-circuits and fires more likely than your model predicted (this is different from most of the rest of my points since it assumes your model is actually correct and unbiased today in some meaningful way but would still fail to be very helpful).

2. The data was just wrong and thus had no bearing on the real world.

3. You have the same fire rate as shoddy manufacturers enter the mix.

4. You have low rates initially, trending toward the same rate we're at now as the cars degrade, except now those fires are incredibly dangerous and toxic.

5. A mandatory software update while you're driving down the road inadvertently triggers a short circuit, leading to unknown-unknowns potentially affecting large swathes of the population at once (unlikely probably, but you are exposed to new failure modes and don't have a ton of data about the rarer ones yet -- much like (1) this isn't actually a criticism of the stats themselves, just their interpretation).

6. When you get more people driving these things in rural, snowy, mountainous regions you get more collisions and fires.

7. Having more teenagers driving EVs substantially reduces any claimed fire hazard deltas.

And so on. Global stats (like fires per crash, per mile, per car, ...) are suggestive of the next place to look for more data when trying to make an informed decision, but when you're talking about something affecting hundreds of millions of people, they're the beginning of the conversation, not the end. That's doubly true when they obviously have some kind of glaring flaw (like the napkin-math observation that they're off by at least an order of magnitude, probably 2 in this case).

Separately, once that data is interpreted correctly, you'll probably find other important observations. E.g., if ICE and EV have the same fire rate excluding shoddy manufacturers, and you have more solid evidence backing that up, that gives you very easy followups. The conversation can shift to the severity of those fires, their mitigations, and whether they're worth the cost given the other benefits EVs have. Moreover, you learn that you can greatly reduce car fires by just having better engineering, so (carefully and thoughtfully) toss in a law or tax or something to try to encourage better behavior.

Similarly, if you find old vehicles are the root cause then you can encourage recycling or rust-proof coatings. That might even be a point in favor of EVs since the batteries don't last long, so they'll be recycled before they're likely to combust (again, assuming for simplicity that everything else stays constant, which a policy-maker hopefully would not).

Just the stats presented though, especially without evidence that the obvious confounders don't apply, would likely not be helpful in making an informed decision. You could do just as well, perhaps better, from a gut instinct, and the presence of those stats in isolation is (charitably) just to help provide to people the data we do have and encourage further discussion, or (uncharitably) to present decontextualized information in a way that biases the populace in an intended direction, despite the fact that it's useless for the stated goal.

I've witnessed this already at the office ..

  Battery electric fires are so rare that most fire men will never deal with one in their careers.

> Calling out long duration storage is another red flag. How much of that is needed? In giga watt hours please. Nobody ever bothers to qualify that.

That includes you. (No numbers just assumptions that all will be fine)

Worth noting that there is no “required” amount of kWh of storage, people can get used to blackouts and/or real time prices spikes and/or adjust habits (reduce usage).

Just to have some numbers:

1kWh of battery costs 139$

US uses 11,267 kWh/year/capita of electricity alone. Thats 30 kWh per day. So 1 day electricity storage costs 4000$/capita of investment.

Total energy consumption in US is 295 million BTU/capita/year, which is 236 kWh/capita/day.

To cover for one day of all energy, US needs 32000$/capita/person investment.

In current setting, Oil/Uranium/wood act as a kind of battery, and we are very used to having large “batteries”. (Some people prepare wood for couple of winters ahead)

https://en.m.wikipedia.org/wiki/Energy_in_the_United_States)

https://www.statista.com/statistics/883118/global-lithium-io...

https://en.m.wikipedia.org/wiki/Energy_in_the_United_States