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Researchers Create Sodium Battery In Industry Standard "18650" Format (gizmag.com)
Zothecula sends word that a French team has developed a battery using sodium ions in the usual "18650" format. Gizmag reports: "A team of researchers in France has taken a major step towards powering our devices with rechargeable batteries based on an element that is far more abundant and cheaper than lithium. For the first time ever, a battery has been developed using sodium ions in the industry standard "18650" format used in laptop batteries, LED flashlights and the Tesla Model S, among other products."
The idea on many small battery cells is that the standard size makes them available from multiple suppliers, reducing risk, and the gaps between the cells due to the packing fraction provide a conduit for cooling.
Telsa does have a lifecycle plan to refurbish packs from cars for use in the home; at least in the press photos, the home packs are a different form factor, so I wonder if they break up the packs to cull outright broken cells and then reconstitute the good ones into wall units. Since the breakdown is a function of electrode area, having the area in smaller pieces might help with reuse.
"Because Science" is one step from "Because old book". Try "Because of my experiment testing my falsifiable assertion".
If you want an actual answer instead of just an excuse to bag on Tesla ... Smaller cells have more surface area to dump heat, which is crucial when recharging. In other words, the mass of the casing (which is not large) is actively being used for thermal management. Additionally, in the manufacturing process, smaller cells have a lower reject rate and allow both a much more repairable battery pack than custom cells and improve the performance as cells degrade. The packing density for these cells is pretty good, (85%) and smaller cells allows tailoring to custom shapes, though Tesla doesn't take advantage of that, having roughly rectangular packs.
Lithium is about as abundant as chlorine. Concentrated deposits occur all over the world with proven reserves of about 14 million tonnes and annual production of 36,000 tonnes. It would be really hard to run out (or create scarcity) of lithium.
I don't read your sig. Why are you reading mine?
Consumer secondary batteries have 10x higher energy density by weight and volume today as compared to 30 years ago.
Your smartphone battery would weigh 1lb, and be 5 times the thickness of your phone, if made using 1980s nicd.
More importantly, the 7000 little batteries actually make the system more efficient than 7 large ones. Because of the massive amount of power the motors have (50+ kW), using more cells in series means higher voltages. And higher voltages means lowered currents which mean less wasted power in IIR losses. Double the voltage, halve the current, one-quarter the loss. It's why transmission lines are high voltage, why data centers usually get 208V or higher (besides three-phase) at the racks, etc.
7 lithium batteries only gets you 28V. If we use 56kW, that's nearly 2000A you have to draw - you probably will have to use the chassis split down the middle to carry that kind of current. 7000 lithium batteries as 7x1000 (4000V) series packs means drawing 14A from each pack, or 98A total. Of course, no one runs that high a pack voltage - safety reasons - it's usually closer to 480V or so, which is a large current but still manageable.
When I first started looking at standard AA batteries in about 1994 you had your normal Zink-carbon batteries that the good ones would be 1200mAh capacity. There were some premium Alkaline batteries that were 2000mAh. If you wanted rechargeable you were looking at NiCd at about 800mAh.
Fast forward to about 2004. Alkaline batteries at about 2000mAh was standard. Lithium batteries at 3000mAh were around and NiMH had almost completely replaced NiCd at about 2100mAh for good quality ones. Then there is also the proliferation of Li-Ion batteries for other applications. Charge times for rechargeable batteries had come way down.
Today Alkaline batteries are at about 2600mAh, with Lithium still at 3000mAh. NiMH are still in use and the good ones are still at 2100mAh with some "Pro" batteries at 2550mAh. Li-Ion still in great use, but getting smaller while keeping the same amount of power. Charging times have continued to decrease, mostly with new charging technology that can be used on the older batteries as well.
What does the future hold? Well, we have heard about tech for making Li-Ion batteries fully charge in minutes. There is the improvement in sodium batteries. Different chemical combinations of Li-Ion to hold more power.
Why is it not here now? Most new technology takes at least 5 years from announcement of it working, to being able to mass produce it at a decent cost. That is for companies that have lots of money and experience in that specific field. More of an average is 10 years between proof of concept and mass production. 10 years may sound like a long time to people, but in the manufacturing world with new technology, it really isn't that long. Intel runs with a 10 year plan, and they can bring many of their advancements to market in 5 years. Intel is a company with a lot of money and a lot of knowledge about exactly what they do and yet, they still work on basically 10 year plans. Most companies are not as efficient.
Yes many times products will be designed and brought to market in 1 to 2 years, but they usually use existing technology. They use chips, tech, batteries that exist when the product is announced. They already have the full design done, all they need to do is mass produce them, and it still takes 1-2 years. Even though exactly how to mass produce it and all the parts are known. New technology on the other hand is a different beast that there are often problems in figuring out how to mass produce it, or they find out that it can't be mass produced cheaply enough.
The other thing is that you are getting the new technology all the time, you just don't notice it because it is done in an incremental process. The battery has a little more power, it is a little smaller, it charges a little faster. Where if you compare something today to 10 years ago you would notice that the battery stores a lot more power, it is a lot smaller and it charges a lot faster.
Microsoft, Apple, Google, Amazon what's the difference? All steal money from devs and control with walled gardens.
Indeed, lithium mining from salars is actually one of the more benign mining processes that exists. You're out on an area that is virtually devoid of life, pumping up saltwater, letting it evaporate in ponds to concentrate it, selectively crystalizing the desired salts (such as lithium salts) out, and setting the remaining salts back on the salt flat. Every year the annual floods come and resurface the entire thing.
You know, sometimes it feels like people just want to hate any new technology.
I hate to bring up our imminent arrest during your crazy time, but we gotta move.
Except...this time it's true. The Gasoline car manufacturers _really do_ own the patents for making large automotive batteries. That's why Tesla has to make do with using several thousand tiny 18650s instead of a few big cells.
https://en.wikipedia.org/wiki/...
No sig today...