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Comment by dtx1 | Hacker News Reader

50 Thousand Cycles would make replacing batteries unnecessary for almost all usecases. I would love such a battery in an electric bike. Max Range would be quite limited compared to a Lithium Version but with 10x discharge capacity and functionally unlimited life you could make a beast of a commuter e-bike.

50000 Cycles would realistically mean you can charge the bike every day for a hundred years

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You can build such a bike today with LTO cells, which are commonly rated at 5,000 - 25,000 cycles (depending on manufacturer) to 80% of nameplate capacity. You'll compromise on range, of course; but in the worst-case corner (extremely low temperature outside, high current draw rate) the comparison to at least LFP is pretty favorable, and you're within a factor of 2x or 3x of NMC throughout the envelope.

Honestly after a quick google search I'm not convinced LTO Cells are applicable for that use case. Best I found on a quick search is 80wh/kg and at a low voltage and good enough but not great discharge capacity. Even in the electrical bicycle range that's just not enough to be practical, let alone competitive.

LFP at it's peak gets you there but it's also not a great experience. The Battery needs to be too large to get you enough current to be enjoyable.

That's why the 10x (even a 3x would do it) in discharge capacity is what get's me excited. That's enough that you can use only a few cells but with enough output to be a nice experience, just with short range.

80 Wh/kg beats the 70 Wh/kg of the cells discussed in the article, which was the benchmark for your proposal. Voltage doesn't really matter at all for this; you just end up with a few more cells in series (though it's admittedly awkward if you're targeting ~56 V max as the top of SELV where most single-chip BMS ICs top out at 18s). And even though most common LTOs are only rated for 10C, they're rated to do that below 0°C, in which domain they absolutely crush the ratings of LFP cells -- for LFP, you end up sizing for temperature unless you're looking at summer riding only. Admittedly you're not going to match 40 C LFP and NMC pouch cells with a cylindrical cell, and I'm not aware of anyone currently making LTO pouch cells; but I do think it seems unlikely that the sodium cells that are the subject of this article bring any really new capabilities to the domain of ebikes.

In industry trade magazines I'm seeing references to automotive batteries that would be good for half a million miles. Typical US driver would take 40 years to drive that far.

Also seeing that companies are serious about actual production of solid state batteries. Which have twice the energy density. I don't see cost numbers but might be those are actually cheaper just because there is less mass to manufacture.

The first generation will work like that.

Then they will introduce various defects into the manufacturing process to decrease the lifespan (and they'll say it's cost) and the batteries will last 10 years max. Maybe 15 if you're lucky.

Why so cynical

I mean, look at what was done to lighting. There are some original Edison bulbs that still work, yet you'd be lucky to get a year out of a modern incandescent. Same thing happened to LED bulbs.

> There are some original Edison bulbs that still work, yet you'd be lucky to get a year out of a modern incandescent.

https://www.youtube.com/watch?v=zb7Bs98KmnY

> Same thing happened to LED bulbs.

Because LED Bulbs cook your LEDs and are stupid design. Get a permanent LED fixture with decent passive cooling and they will last for decades. Adapting LEDs into the same Plug as Incandescent lighting just does not work.

I've actually found that LED bulbs have only gotten more and more reliable over time. I used to have to replace them regularly but I haven't had one fail in several years now. And permanent LED fixtures are the stupid design. Who wants to do electrical work every time your light fails because of a power surge/lightning strike/capacitor going bad/whatever?

I don't know where you are from but here in Germany Surges/Lightning Strikes that damage equipment are so rare that I can't remember it ever happening to me in my lifetime. And Replacing a fixture if it eventual fails after decades is just not that hard. I did it in my Appartment and I only shocked myself twice, so it's very doable.

I stand corrected.

The tradeoff with conventional light bulbs is efficiency vs. lifetime. This is not the usual planned obsolescence it is made out to be, you are actually getting more efficient bulbs that way.

Want the experience of a lightbulb from 100 years ago right now? Buy a 220v lamp and use it in a 110v circuit. It will be much dimmer, a lot more orange/yellow, and last for decades.

The market for cost effective grid batteries is gigantic. There is no need to self sabotage.

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