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Anthony F
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You guys are all wrong - you're thinking too big! 30 seconds of charge for 10-30 minutes of activity sound likes a great application for R/C cars and other entertainment devices. ;)
I'm glad to see Sion Power improving their cells. The next step-change for Tesla cells will be the 2170 cells for the Model 3 - I expect a significant increase (probably over 300Wh/kg and 800 Wh/l). The key that Tesla invested in with the P100D is the increased pack volume efficiency - the same size pack can hold more cells because of cell and cooling layout. This is needed for the Model 3 to hold all the cells for the high-capacity battery pack. A 500/1000/1000 (Wh/kg, Wh/l, cycles) cell would be insanely great, but I don't expect them in any time frame I would plan an EV around (3 years). That said, with the increased packing efficiency of the new Tesla packs, you're looking at dramatically cutting pack weight as well as extracting 20% more energy per unit volume. An future Model S pack (assuming similar volume) could hold 120-130kWh of energy and weigh 150kgs less. Or just hold the same 100kWh and weigh 200kgs less. And 1,000 cycles at 350 miles per cycle is 350,000 miles to 80%. Its really higher than that because, at least with today's Li-Ion batteries, the more shallow the cycles (e.g. 60% to 40% five times vs. 100 to 0 once), the less strain it has on the internal battery structure, so you'll get more than 1,000 cycles to 80% capacity reduction.
It might take 5-10 years before cells like this work their way out of a lab, through the proof of concept stage, and into the manufacturing world and into products you can own. But the future for batteries looks bright. Its not a matter of if but when.
Pretty sure the poor energy/power specs are to compensate for the high cycle count.
Interesting the report pours cold water on Li-S batteries. There has been a lot of research, and I believe they may be preferable for aviation due to their light weight and relative availability. Also, it mentions the change in focus of the EV battery markets - away from how much the batteries weigh to how much volume they use. The smaller the physical pack, who really cares how much it weighs now that most battery manufacturers have managed to get close to or exceed the 200Wh/kg metric (cell level). Further gains to 500+ Wh/kg aren't needed more than increasing cell density up above 750Wh/l to fit in appropriate sized cars.
Maybe we should call this the LG Volt instead of the GM Volt if they're making so much of the product.
A 20 year life cycle is great for grid storage, but not useful for EVs and electronics. The battery shouldn't outlive the device its in. A 50% reduction in price for grid storage (down to $100-125/kWh) is a big win though, combined with a 20 year life cycle, that brings down the cost to about 2c/kWh which is about the price difference between peak and off-peak.
"Double the energy content" probably 400Wh/kg, there may be many SSB by 2020 that meet or exceed this. "75% smaller" This is more impressive, probably somewhere north of 1500 Wh/l. This is probably what they are looking for if they want to go after the hybrid/plug-in hybrid market due to space constraints. A 5 liter battery would store more than enough energy to raise MPG to comply with tighter fuel economy standards.
The poorest individuals generally aren't homeowners or able to afford a vehicle. So they're not likely to see any benefit from these programs as designed. If you were to restrict the population to those eligible to receive credits (e.g. A homeowner or a household that owns at least one car) then I think the numbers would be more informative. Also, I am curious if the study accounts for leases in the PEDVC calculations. An individual with more modest income may choose to lease an electric vehicle because he or she doesn't have the $7500 of income tax to rebate if they were to buy the vehicle. While the leasing company ends up receiving the tax credit, the individual leasing the car sees the benefit through a lower lease rate. Honestly, if the authors are interested in positive environmental outcomes and distributional justice, then maybe they should just be campaigning for massive federal subsidies for mass transportation to the point where it's free for everyone.
As corporate and government fleets gear up for 200 mile EVs due the next few years, lower power quick chargers will become a lot more common. Running a 100kW main and then having four quick charging stations is probably the most economical route for EVs that need to be charged quickly (full charge in 3 hours, 100 miles in 60 minutes).
My GE charging station isn't living up to expectations - its randomly refusing to charge my Volt, usually when its hot or cold outside (even though the station is inside the garage). I'm looking forward to replacing it with a WiFi-connected unit, and I trust Chargepoint a lot more to build a charger that works reliably (I've never had an issue with the Chargepoint charger, indoors or outside).
180M gallons per year sounds like a lot, but the US aviation industry used around 16B gallons in 2014. So that 180M is about 1.1% of total usage. A good start but we're going to need a lot more than that to make a dent in both the price and the impact of oil.
Lad: I was quoting cell-level specifics. I think the 600lbs figure you quote is pack-level. So I don't think it translates over as easy as that. I do think that the next Leaf will likely be around 250Wh/kg at the cell level (the battery in my iPhone 6 is 250Wh/kg!) but how well they construct their pack and the efficiency will determine how far it can go. I think they'll get somewhere around 150 miles (EPA) on a 42kWh pack.
SiC inverters are going to have a big impact on electric transportation, but they aren't mainstream, and probably wont be for several more years (2020). I asked GM during one of their FB chats about it, and they seemed to indicate it wont be coming anytime soon (and its definitely not in the Gen 2 Volt).
No specifics on what exactly these Li batteries would be suited for (grid storage, EVs, small devices, etc. - though the image in the linked press release seems to indicate a larger format for grid storage or EVs). That said, they really don't need to improve on the performance characteristics of batteries of today by that much. The cells in the Tesla battery pack are 250Wh/kg and 700Wh/l, and an 85kWh pack can produce over 500kW of power (691hp in the P85D), and a pack life (to 80%) somewhere around 125,000 miles. Batteries that had those exact same characteristics but cost $100/kWh would still enable the widespread adoption of EVs - a 50kWh/200mi pack for a smaller car would cost $5,000 instead of $10,000+. But one only needs to look at the curious tale of Envia, which promised us 400Wh/kg batteries by 2014 to know that the battery industry is susceptible to immense hype.
What is the penalty? Increased $/kWh? Decreased power? EV batteries don't need to last a million miles. 3000 miles x 100 miles is 300,000 miles. Thats plenty for one pack. By the time the pack is exhausted, there will be a much better pack to plug into your EV. This makes great sense for grid storage though. Improving the cycle life of the batteries at 100% DoD will greatly reduce the cost per kWh of energy storage. If you can cycle a pack at 9,000 cycles to 80% instead of 4,500 cycles, you're cutting the per kWh cost from roughly 15c to 7.5c. 7.5c is close to the actual difference between on-peak and off-peak times.
IIRC, the Malibu pack is 1.5kWh, so that's 78 of these cells, or 18kg of cells (plus harnesses, wiring, module, pack, thermal). At 5kW/kg, that's 90kW of power from this small battery pack. Impressive!
Isn't Tesla selling the 100kWh PowerPack at $250/kWh? Granted the balance-of-system costs will differ slightly for stationary battery (still needs cooling but maybe not as much ruggedized) versus EVs (need a pack that can withstand 150,000 miles of being driven over rough roads). I would presume they're not losing money on each PowerPack they sell, and probably have a somewhat comfortable margin (shareholders might get pissed if they can put those cells into cars that make 28% gross margin vs less than 10% margin on stationary storage). I'd venture to say that Tesla is at $250/kWh (pack) today, and will be at $175/kWh by 2020 (30% reduction) after the GF1 is up and running at near full capacity. By 2025, they will be under $150/kWh (another 15% reduction).
I agree that 2kW continuous and 3.3kW peak is rather low. I think these first-generation units will supplement grid power, not replace them. Its the Tesla Roadster of home battery packs (you buy one to have another car, not to replace your daily driver). If your house is pulling 4kW, then you'll get 2kW from the grid and 2kW from the battery. If you want more then buy more and daisy chain them, but I doubt it'll be economical at anything less than grid-scale applications with industrial inverters that get 95%+ efficiencies.
97% initial capacity retention after 1,000 cycles is more than adequate. Batteries that will never cycle out are ideal for grid storage, lowering the cost per kWh stored when amortized over 10+ years.
Its great to see GM move so swiftly to introduce the Bolt (though it needs a name change). Especially since they could have withered and said that demand was lacking because of low gas prices (which we all know is a temporary situation). Being the first to market with a 200+ mile EV that isn't a high-priced Tesla is a big win for GM.
500L = 132 gallons. Two 66 gallon tanks have to be huge - how are they fitting those in the vehicle?
I suppose the good news is that these future battery targets are getting closer - instead of 3-5 years for commercialization, now its 2-3. Lets see if they can actually get it into mass production! 1200-1300Wh/l is a 50% or so boost over current batteries, plus any benefits of reduced cooling or safety that these SSBs provide.
Going after the consumer market first is a good idea, it allows you to work on scaling up instead of having to go from 0 to 1GWh/yr for an automotive application. As long as Apple keeps wanting to make iPhones slimmer and slimmer (a safe bet), higher Wh/L will be necessary to cram all that energy into a thinner and thinner space. The iPhone 6 battery has about 575Wh/L, so getting up to 700 or 800 would bring an extra 30% battery life.