241st ECS Meeting: Keynote Speake Jeff Dahn

The plenary session is a highlight of every ECS meeting, bringing participants from all symposia together to celebrate some of the greatest minds in the field. Hear Keynote Speaker Jeff Dahn's talk on “Modern Lithium Ion Batteries: More than One Million Miles and Possibly a Century of Life.”
Learn more here: www.electrochem.org/241/plenary

[@investingthelike111]

18:30 What's important , avoid large volume changes , use best graphite, appropraite electrolytes , 23:50 LFP vs nmc , 25:30 best nmc vs best LFP , 28:10 lower voltage means nmc 10x battery life plus high energy density , 31:12 testing at 70degrees (nmc wins) , 31:50 tempreture matters , 33:50 100 year battery , 35:43 nmc at 85 degrees , sodium ion batteries important,

[@kemallette]

Thank you for posting this for folks like me to watch. 100 year battery. Just incredible!

[@rogerstarkey5390]

Just an observation, but the best question (imo) came from the youngest and last participant.

[@Tim_Small]

@6:15 this does look bad (and it is), but it's worth remembering that transport by direct electrification uses 50% to 80% LESS primary energy than fossil fuel transportation, and production of low grade heat by heat pumps also uses 50% to 80% LESS primary energy than just burning fossil fuels. So the real energy demand is likely half or less than the graph suggests.

[@investingthelike111]

bravo

[@redhammer9273]

24:27 LMAO

[@investingthelike111]

not sure if this was answered, what if you only charge the LFP with LiFSI to a lower voltage? like 3 volts would that make them last longer? or does the degradation only happen to either battery at around 3.8 volts and above? EDIT: the answer may be that degradation only happens with a large volume change in the battery which does not occur with LFP

[@JRP3]

Also LFP at 3 volts doesn't have much capacity, maybe around 20%.

[@Kangenpower7]

Thanks for letting me know that my first electric car should be charged only to 70% on a daily basis, and 80% on rare times, and 90% only when required. And that fast charging - I should do it before getting to 10% state of charge. I think I will also be looking for a 150 KW charger, even if my car says that 280 KW is fine with the car. Lets say the F-150 Lightning is a $150 per KW battery pack and 135 KW. That is a total cost of the battery pack of $20,250. So if Ford felt they could sell that truck at $40,000, and I could somehow convince them to reduce the battery pack by about 40% to 81 KW, X $150 per KW would be only $12,150. I would love to have a truck that is $12,150 less expensive, even if I can only drive it 90 miles a day! I have never driven more than about 45 miles in any one day in the past 2 years! My trip to Medford Oregon, from Portland at about 300 miles would take 1 recharge with the larger battery, or 2 charges with the smaller and easy to afford battery. I would love the lower cost vehicle! Tesla is planning on releasing information about a new car, with a $25,000 - $30,000 price tag. I am hoping that the battery might be smaller, and thus make the car more affordable. I would love a 2 passenger car to drive to work and home, not needing the back seat for most of that driving. A 35 KW to 55 KW battery should be fine, if the vehicle is about 2,000 pounds? Would that be possible? I was also thinking about a very low cost car that the workers in China could afford and drive to work, and be produced by the thousands! Perhaps a three wheel, with two wheels in the front, and front wheel drive, with the battery pack under the center console of the car, say 12" wide and 60" long, so there will be more weight on the rear axle. Maybe they could have a cast front end and a fiberglass body? Very easy to assemble vehicle. Keep it at about 2,000 pounds, and it should have a great range, even with a 35 KW to 50 KW battery pack. A cargo version would have just the drivers seat and a storage area on the right hand side, for pizza delivery, or flowers or whatever! I know a HVAC distribution company that would love one to deliver parts to the customers (the contractors making a repair at someone's home) who are at the residential homes of their customers. (the contractor loves it that the technicians are not spending a hour going to buy a part to make a repair, but instead can order the part, and have it in their hands within 90 minutes! ). The HVAC distributor loves that the customer is getting the parts quicker, and selecting them to sell the part to them, delivered, and in a short time! So overall their business is up over 50% due to the delivery service. There are a lot of potential EV buyers who are saying "Why not install a 40 KW larger battery?" The answer of course is that the extra 40 KW is about $150 per KW, or a $6,000 option that will also make the car mush heavier. If Tesla has cars going 250 watts per mile, that would mean a 50 KW battery is good for 200 miles between recharges. Or about 160 miles when charged to only 80%. That is fine with me, I never drive 100 miles in one day. And if the Tesla fast chargers are located every 100 miles along I-5 in Oregon, I can run 100 miles, charge for 8 minutes, then run 100 more miles. Put a couple of fast chargers in Ashland, on the hill going into California, and I can make it to Weed, where I can charge again on the other side of the mountain.

[@xlargetophat]

Cool

[@JRP3]

A few things I somewhat disagree with. 400km, (250 miles), is enough range in ideal conditions but it can get cut almost in half in extreme cold and snow. Extreme cold also slows down charging speed. For those reasons a 500+km pack is desirable. Additionally a larger capacity pack will have fewer cycles per miles driven and cycles for supporting the grid so it may make sense to sacrifice some cycle life for capacity.

[@georgepelton5645]

Yes. My first thought was that 400 km is sufficient, but 500 km does make a more desirable car. In below freezing temperatures I don’t drive as much or as far, so even half range (200 km) is plenty for everyday driving. I believe that driving less when below freezing is common, not just my habit. However, for long trips the extra range of a 500 km, or even 600 km, car is a benefit. The longer range allows a greater choice for when and where to charge. To make EVs affordable to all new car buyers, I like Jeff Dahn’s approach with 400 km range, zero growth in internal resistance, and >25 year battery life. Someone needs to build such a car and offer 15 year warranty on the battery and drivetrain. At the price of an IC engine car, no one would hesitate to buy.

[@georgepelton5645]

BTW, Great talk by Professor Dahn, as usual. 😀

[@JRP3]

@@georgepelton5645 Actually for an affordable car you want the most range from the least amount of batteries so it might make sense to not worry about 25+ year capacity retention and push the peak voltage higher. In truth what Tesla does seems ideal, let the user set the charge percentage, that way in every day use you can charge to a lower voltage but still do a 100% charge at a higher voltage for longer trips when needed. 99.99% of the time I don't charge beyond 85% and I only do that about once a week so after my first drive the pack is sitting at an even lower voltage most of the time.

[@Kangenpower7]

I disagree with the need for over 200 miles of range. You can spend 10 minutes recharging and get that extra 50 miles in that time, while installing a 40 KW smaller battery pack. $150 per KW X 40 KW is a $6,000 option! If I could buy the F-150 without that 135 KW battery, I would rather keep that $6,000 in my pocket, and make it possible to buy a EV. If the price is to high, I would never be able to afford a EV, so the smaller battery is great for me. On a 200 mile trip, you would need to charge one more time with the smaller battery. On a 300 mile trip, 2 more times. But overall it is not that big of a deal, as long as the car is something I can afford to buy.

[@JRP3]

@@Kangenpower7 You ignore the fact that your 200 mile range becomes closer to 100 miles of range in severe winter conditions or while towing. Also most people would like to be able to drive 3-4 hours without having to stop.

[@investingthelike111]

if you need to go more then 400km , just get a bigger battery pack

[@tophat2002]

When making the vehicle in the factory.. a bigger pack would unnecessarily effect the price if you don't account for other factors at the design stage.

[@investingthelike111]

@@tophat2002 long range plus

[@bfmarx]

Novonix

[@stevew5212]

Why use water? Rocks and rail road tracks would be much better and can be made in many places. Take the rocks to the top of the hill on railroad tracks. When we need the power, start sending the rocks down the hill on the rail road tracks.