New Battery Technologies

[Pizzazz]

I came across this article below about Tesla's new battery technologies. The article suggests that the cost of lithium iron phosphate battery packs has fallen to $80/kWh while nickel-manganese-cobalt battery costs are around $100/kWh.

https://apple.news/A0FsPnr0bTymIzcddAz9v5w

According to my calculations, a wet cell golf cart battery that costs $100 at Costco (probably $50 wholesale) has around 208 x 6V = 1.25 kWh of max energy capacity, probably around 1 kWh max useable. I do understand the difference between retail, wholesale and Tesla's prices but if the above is true the cost of the latest lithium battery technologies is roughly equal to the standard wet cell golf cart cost. We should expect that in the next couple of years lithium batteries will become available to us at these price levels.

My suggestion would be, hang on to our current golf cart setups for a little longer and then the market will be flooded with low cost lithium batteries. Furthermore, if these batteries can accept the high charging rates that Tesla cars can accept now, it would be really interesting to see a fast charging solution (imagine that we can get some sort of an AC style alternator, mounted directly on the engine or the gearbox, that can make 10 kWh (in neutral), so you run your engine for 15 min and your batteries are fully charged). Forget about slow charging solar, forget about current expensive lithium batteries.

SV Pizzazz

[lonesoldier0408]

Originally Posted by Pizzazz

I came across this article below about Tesla's new battery technologies. The article suggests that the cost of lithium iron phosphate battery packs has fallen to $80/kWh while nickel-manganese-cobalt battery costs are around $100/kWh.



https://apple.news/A0FsPnr0bTymIzcddAz9v5w



According to my calculations, a wet cell golf cart battery that costs $100 at Costco (probably $50 wholesale) has around 208 x 6V = 1.25 kWh of max energy capacity, probably around 1 kWh max useable. I do understand the difference between retail, wholesale and Tesla's prices but if the above is true the cost of the latest lithium battery technologies is roughly equal to the standard wet cell golf cart cost. We should expect that in the next couple of years lithium batteries will become available to us at these price levels.



My suggestion would be, hang on to our current golf cart setups for a little longer and then the market will be flooded with low cost lithium batteries.



SV Pizzazz

I’ve noticed a decline in fuel prices and increases in other areas. All things being in flux leads me to the conclusion that the time to address it, is before you need it. However, we always seem to do it, after we are out of time for the analysis.
With the bailouts and stimulus packages, inflation will offset any savings to be had by waiting. The dollars of next year will be worth less than any of the previous years.
Respect, for your insight, I’ve just had a year that emphasized my lack of time.

[ssmoot]

Originally Posted by Pizzazz

Forget about slow charging solar, forget about current expensive lithium batteries.

Just some thoughts as an amateur DIYer.


I bought 15kWh of LiFePO4 for $3,250 a couple months back. Or $217/kWh. I've seen $174/kWh, and some better deals here. It'll get cheaper. You can probably take another 20% off overnight in a year if the Trump Tariffs go away. So I expect prices will steadily decline to a point, but not hit the $100/kWh mark for NMC/NCA cells the EV OEMs are aiming for.


See the graph on this page: https://www.motortrend.com/news/tesl...harger-tested/


The Tesla Model 3 charges at about 4C for 5 minutes at a low SoC. By 25% SoC it drops to a 2C rate and at 55% SoC it starts dropping linearly hitting 1C around 75%.


That's not particularly remarkable with this chemistry, but if you do that type of charging routinely you'll quickly be looking at dramatically reduced cycle life that will result in a much more expensive 10-year TCO. NCA cells are also not safe. Sure they don't pop-off as frequently as a fuel line might leak on a gasoline engine, but when they do you're losing the entire boat.


If that happens anywhere offshore you can only imagine the consequences. It's a very very bad idea. Given you can pick up 70kWh of LiFePO4 for about $12K these days, you're risking your boat and your life for pennies on the dollar.


I've only recently gotten back into looking at cell options, but things have come a long way in the past few years in the LiFePO4 market. Lighter, smaller aluminum cased cells substantially cheaper than they've ever been. If you're looking to build a house or propulsion bank, it's a great time to be shopping IMO (though Summer 2021 is probably better!). Keep the automotive chemistries on the dingy where weight and charge rate is more important, and safety, cycle life and other concerns less so.

[ahbklmng]

Originally Posted by ssmoot

Just some thoughts as an amateur DIYer.


That's not particularly remarkable with this chemistry, but if you do that type of charging routinely you'll quickly be looking at dramatically reduced cycle life that will result in a much more expensive 10-year TCO. NCA cells are also not safe. Sure they don't pop-off as frequently as a fuel line might leak on a gasoline engine, but when they do you're losing the entire boat.


If that happens anywhere offshore you can only imagine the consequences. It's a very very bad idea. Given you can pick up 70kWh of LiFePO4 for about $12K these days, you're risking your boat and your life for pennies on the dollar.

One of the big things expected out of Tesla's next battery version is that it will be cobalt free, and the fire risks you are referring to become non-existent. The chemistry is also expected to be the so called "million mile" chem that can handle thousands of discharge/recharges without degradation. Not to mention the higher density and lower costs from things like removal of the tabs (also helps to keep temps lower) and improved manufacturing techniques.

I'd recommend reading the paper "Is Cobalt Needed in Ni-Rich Positive Electrode Materials for Lithium Ion Batteries?" from Tesla researches for reference.

Also, the youtube channel The Limiting Factor is an excellent resource that does deep dives into the tech.

Check out the video on Tesla's tabless patent, which was filed last year and just came out.

LINK

There's also a whole series of vids on what to expect from Tesla's battery day.

LINK

My take is that just like solar ten years ago, people are exponentially off in their predictions of how fast the improvements in performance and cost reductions will be for battery storage solutions. We are already at the 2035-2040 performance/cost predictions from ~2010 for solar in 2020 for example (source). In the next five years, the option to go solar/battery/regen will be compelling and without near as much range sacrifice or cost as we have today if at all.

[ssmoot]

Originally Posted by ahbklmng

One of the big things expected out of Tesla's next battery version is that it will be cobalt free, and the fire risks you are referring to become non-existent. The chemistry is also expected to be the so called "million mile" chem that can handle thousands of discharge/recharges without degradation.

Tesla also claims they'll sell a 500 mile battery electric truck, and a 620 mile sports car while falling far short of their range claims on their existing vehicles.


Tesla doesn't make batteries. None of the batteries in any Tesla vehicle ever sold were manufactured by Tesla. Lab experiments that aren't replicated in a manufacturing line are interesting, but not indicative of much or we'd all be using solid state batteries.


"Battery Day" is a stock pump. Just like "Autonomy/Robo-Taxi Day" and all the other pumps before it. Nothing more.


The cobalt free batteries you refer to are CATL LiFePO4 cells. So everything said still applies (and these are prismatic, not cylindrical as far as I'm aware, so the tabless patent application doesn't apply). Do not put today's "Tesla" (Panasonic) batteries on your boat.


"Million Mile" is just rebranding/marketing the cycle life we're all already familiar with. If you believe a Model S can get 400 miles on 100kWh, then you only need to hit 2,500 cycles.


Just buy today's LiFePO4. Will tomorrow's LiFePO4 cells be better than today's? Probably. But only marginally in energy density. The real developments will come in improved C-rates. Which doesn't matter much on a boat when none of your charge sources is likely to exceed C/2.