Amid a packed afternoon of bulletins from Tesla round improvements the corporate is pursuing to slash the price of electrical automobile manufacturing and vitality storage via higher battery design, the corporate mentioned it’s made new developments in materials science for anodes and cathodes — key parts of the lithium-ion batteries which might be the center of all of its merchandise.
Tesla took an all-of-the-above strategy to enhancing its battery from the manufacturing course of that’s nonetheless below growth to the supplies utilized in cathode and anode, the fundamental constructing blocks of any battery system.
The upshot: a discount in value of the cathode and anode supplies, whereas boosting efficiency that by itself might lengthen the vary of its batteries by 20%, Tesla mentioned.
On the anode aspect, the corporate is taking a look at methods to combine extra silicon into its batteries by utilizing metallurgical grade silicon. One of essentially the most plentiful supplies on earth, many of the silicon utilized in microchips, batteries, and even photo voltaic panels has been extremely processed utilizing costly remedies to make it work for various functions. With batteries, the problem is its propensity to degrade when it’s totally charged with lithium.
“With silicon, the cookie crumbles and will get gooey,” mentioned Elon Musk throughout the firm’s “battery day” presentation. That gooeyness signifies that the fabric loses its vitality retention and storage capability. Every time a battery expenses, the degradation means shorter life cycles for the battery.
That’s why most firms use some type of remedy on silicon to make the fabric hardier — or use as little silicon as doable of their batteries. “They allow among the advantages of silicon, however they don’t allow all of it and so they’re not scalable sufficient,” mentioned Andrew Baglino, the corporate’s SVP of powertrain and vitality engineering.
Instead of throwing the silicon out, Tesla mentioned it’s working with a brand new remedy technique that may take low-cost, metallurgical grade silicon and incorporate that into its new battery designs.
“What we’re proposing is a step-change in functionality and a step-change in value and to go to the uncooked metallurgical silicon itself,” mentioned Baglino. “Design for it to develop [and] consider it within the electrode design … If you employ easy silicon it’s dramatically lower than the silicon that’s utilized in batteries right now.
Baglino expects that by utilizing new remedy strategies, the corporate might drop the associated fee to $1.20 a kilowatt hour.
That includes beginning with uncooked, metallurgical silicon that’s stabilized with a low-cost, elastic, ion-conducting polymer that’s built-in into the electrode with a extremely elastic binder.
That innovation alone might enhance the vary of Tesla autos by 20%. “When we take that anode value manufacturing, we’re have a look at a 5% dollar-per-kilowatt discount on the battery pack degree,” Baglino mentioned.
But the corporate doesn’t intend to cease on the anode. It’s additionally taking a look at utilizing totally different materials science improvements to extend the effectivity of the cathode too.
Both the anode and the cathode want to have the ability to keep their construction whereas having charged particles bounce off of them. They’re principally storage containers for electrical energy at the same time as that electrical energy is transferring round — charging and discharging.
Baglino and Musk likened the supplies to bookshelves, the place the charged particles are the books and the cabinets are the cathodes.
Batteries on this analogy are principally libraries, the place the cathodes retailer the books and the anodes are the librarians transferring the books (vitality) out into the world the place they are often learn or used (I believe I’ve taken that analogy about so far as it will possibly go).
“You want a secure construction to include the ions. You need a construction that maintain its form with ion. As you progress the ion backwards and forwards you lose cycle life and your battery capability drops in a short time,” mentioned Musk.
Several totally different supplies can be utilized as cathodes, however the least expensive, by far, is nickel. It additionally has the very best vitality density. But most batteries use cobalt as a result of it’s a extra secure materials.
Tesla mentioned right now that it’s engaged on a technique to stabilize nickel to be used as a extra strong storage materials. That means the nickel can retailer the vitality (books) with out the danger of toppling or degrading.
“We can get a 15% discount in cathode greenback per kilowatt hour,” mentioned Baglino.
Musk mentioned that Tesla wouldn’t be throwing out its current chemistries, however that the addition of recent nickel-based batteries would allow the corporate to pursue a few of its different targets.
“We must have a three-tiered strategy to batteries,” Musk mentioned. “Iron — medium vary, nickel manganese as medium-plus, and excessive nickel for the Cybertruck and the Semi.”