Mitch Gregory

I just shared a 2170 Li-ion #battery cell teardown. I hope you learn something from my first teardown thread. Huge thanks the @DalRESL for guidance on safety and lab equipment. I think I caught the cell dissection bug… this was awesome! #Lithium #ElectricVehicles #renewables

@evclinic How can you argue model 3 batteries are the best because they are repairable when you have to replace 25% of the pack when a single cell group fails?

Which battery is the best!? A question even the industry cannot definitively answer, and the answer lies at the end of its life cycle. Without sampling failures, creating solutions for a large number of battery systems, and reaching the final destination, i.e., recycling, it is very difficult to determine which is the best. However, we have summarized the answer into a very brief description based on what we have been analyzing for nearly 5 years. The best battery system in the world is one you can repair cheaply/quickly, and the best battery cell is one that is readily available and still usable for a second life. The picture shows the quarterly collection of battery waste that is unusable for any other secondary or tertiary application and must undergo a demanding recycling process into raw materials. In the picture, you see around 300kg of Lithium and NiMH cells, 90% of which are mostly Pouch cells, the rest being Toyota Lexus overheated and overcooked junk in a poorly designed battery system. The remaining smaller quantity is Prismatic NMC, mostly from Hybrids, and in hand are defective Cylindrical cells where we repaired 2 battery systems in a Tesla. Yes, only 4 cells. What the industry has now realized but lacks the courage to talk about, is the new taboo topic that Europe completely missed the mark by using the worst possible cell for battery systems, which is the Pouch cell. The Pouch cell has proven to be very unreliable, complicated for industrial assembly, and unreliable in the long term for any application in the automotive industry. The problem is that each manufacturer designs its form factor, making repair impossible due to the lack of replacements. Another issue is the high degradation and intolerance of cells to high C-rates, i.e., higher discharge and charge currents. Almost all battery systems where repairs were very expensive or impossible involved these cells. Today, everyone understands: Porsche, Hyundai, Kia, BMW, and some others, that the only correct path is a battery system with Cylindrical cells, precisely the cells the entire legacy industry mocked. Now, those same ones who mocked are switching to cylindrical, 16 years after realizing that Tesla was right. The system is more durable and easier to repair, cells are easily available and replaceable. One of the easiest and cheapest battery systems to repair is the Tesla Model 3 LR and SR with cylindrical cells, simpler than the Model S. The smaller amount of problems we encounter are with Prismatic (LFP or Blade) cells, which are more common in Hybrids where the battery systems are poorly designed and exhaust their 2000 cycles in 50k km, and are more expensive than an 80kWh EV battery. In the future, probably everyone will switch to Cylindrical where performance is crucial, and to prismatic/blade where profitability is important. The future certainly brings exponential growth in the quality of these cells, so the need for battery repairs or cell replacement will be greatly reduced. Systems are getting better and higher quality. This is already visible, if we ignore some factory recalls, but one thing is certain, there are very few defective batteries now and there will be even fewer in the future. Completely contrary to mainstream media misinformation and fearmongering (as seen in Auto Klub). The bigger problem will be electric motors and other systems, as is already the case. So in future if you are looking for reliablity and performance, you choose cylindrical cell pack, if you need reliable cheap hatchback, choose prismatic/blade.

@elecclassiccars What does it use for CCS communication control?

Now that’s not something you see every day. A 1969 VW Crewcab with a Tesla 100kWh battery and drive unit. 😉😎 #vwbus #electricvw #voltswagen

🧵Here's a thread about an obscure economic theory from a century and a half ago, which is about to become a MASSIVE deal. ⚡️It helps explains why tackling climate change is going to be v v hard. Some say impossible. The story begins with this building👇

Always fun to open up a new pack! #Tesla #LFP #noCo

And here's the full rack and stack of 4 packs in our dedicated mixed battery array test chamber. Now to control them all uniquely based on a grid storage signal!

This is so cool! Max Rastelli in Halifax, Canada is using his F-150 Lightning as a mobile charging station to grow his e-scooter business. He charges the scooters w/ Pro Power Onboard, which has helped him expand his fleet. Awesome to see the unique ways people are using their vehicles!

@DalRESL The lab can eat its own weight in cupcakes. Happy Birthday!

The RESL team treated me today!

Many claim that 🇩🇪 Germany imported more electricity after the last nuclear power plants were shut down in 2023, but the reality is much more complex, as you can see in the chart below for all of 2023. For example, Germany supplied 10.5 TWh to 🇫🇷 France and imported 9.1 TWh in 2023. So the claim that Germany imported nuclear power from France is not wrong, but we exported even more, and more renewable energy to France than France has in its grid. 🇩🇰 Denmark exported mainly with wind-generated electricity to Germany (13 TWh) while Germany exported 3TWh to Denmark. That makes sense because Denmark can't store the partly massive surplus of electricity as they have a lot of windmills. Electricity generation from coal-fired power plants in Germany in 2023 also declined after the shutdown of nuclear power, even though this does not fit the picture that many would like to see confirmed. energy-charts.info/charts/import_…

Wow. The Dahn lab visits the RESL lab. What a great day. All student hosted. So much fun.

@alex_avoigt Thanks for posting. Where are you getting this data from?

Tesla Semi #3 made an impressive 1.076 miles yesterday (Wednesday) that's 1,731 km for lower costs per mile. Whoever is still claiming you need Diesel or Hydrogen is wrong. And no, it doesn't matter if it was fully or partially loaded as most trucks are not fully loaded anyway. According to available data, the average load factor of truck above 6 tons is in Europe around 50%.

Just another great day bringing in new equipment for a project with Litens. As per normal. We are stacking vertically to save space!

Proud to be part of this community. The @DalFSAE DMS-23 EV is about so much more than building a race car. Its about enabling a community of students to become skilled in everything from circuit design, to metal machining, composites, prototyping and so much more.

First contact attempt, Dec,30 at 00:37:55 AST with 8 degree elevation from #Halifax Downtown HALO station

@loris_nano, Atlantic Canada’s 1st #satellite is scheduled to be launched this Tuesday onboard #SpaceX-26 flight. Tue, Nov 22, 3:54 PM EST Watch the event live! @dssLabs @DalEngineering @DalhousieU @allnovascotia @EngineersNS surl.li/dtppx #cubesat #NovaScotia

In pursuit of our mission, today we are opening up our EV connector design → tesla.com/blog/opening-n…

Canadians now burn more fossil fuels per person than any other member of the G7. Every other G7 nation has reduced their climate pollution since the 90s. Canada has ramped up fossil fuel expansion & emissions. And we’re still debating about TMX. Ridiculous.

@ate_alien Nice. Spread the word.

@MitchGregory2 I'm always telling people that the resulting capacity imbalance limiting the group to 205Ah or 90% SOH on a 1.5C cycle is much worse than losing just the 2% capacity contained in the cell.

I call it the Leaning Tower of Tesla… We encountered a single disconnected cell in a 46P cell group. The resulting capacity imbalance limited the group to 205Ah or 90% SOH on a 1.5C cycle. That’s much worse than losing just the 2% capacity contained in the cell.

@Taiga_Motors Very cool to see! 🇨🇦

Our 2022 Orca marks the world’s first electric personal watercraft sale, as our company continues to ramp up production, furthering our legacy of being a pioneer in the electric powersports industry. newswire.ca/news-releases/…

The ATLAS Summer Academy provides each participant with 70 face-to-face hours of experience in an applied STEM field, through the comprehensive planning and design process of building a functional satellite. Learn more from our website atlascubesat.ca/index.html today.