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Tesla-funded researchers discover surprising detail about lithium-ion battery discharges
A potentially crucial reason behind lithium-ion batteries’ tendency to self-discharge has seemingly been discovered by researchers at the Tesla-funded battery research center at Dalhousie University. What’s quite remarkable was that the group’s findings were amazingly simple yet potentially profound.
Electronic products such as smartphones and laptops tend to self-discharge over time. It’s an all-too-familiar scenario, where a device loses battery charge despite not being used for a period of time. But while this is considered normal today, researchers from Dalhousie University may have discovered the culprit for self-discharging lithium-ion batteries.
Dr. Michael Metzger, an assistant professor and the Herzberg-Dahn chair and in the Department of Physics and Atmospheric Science at Dalhousie University, noted that a commercial tape that holds electrodes together in lithium-ion batteries could be a key contributor to the self-discharging process.
“In commercial battery cells, there is tape — like Scotch tape — that holds the electrodes together, and there is a chemical decomposition of this tape, which creates a molecule that leads to the self-discharge. In our laboratory, we do many highly complex experiments to improve batteries, but this time we discovered a very simple thing. It’s a very simple thing — it is in every plastic bottle, and no one would have thought that this has such a huge impact on how the lithium-ion cells degrade,” Dr. Metzger said.
To understand lithium-ion battery cells and their self-discharging behaviors, Dr. Metzger and his team opened up several cells and exposed them to various temperatures. To their surprise, the team found that the electrolyte solution in the cell was bright red. Exploring further, the team placed cells with common electrolyte solution into ovens at four different temperatures. Four different oven temperatures were used, ranging from 25°C to 70°C. The cell sample at 25°C remained clear, while the sample at 55°C turned light brown, and the one at 70°C became blood red. The team then performed a chemical analysis to examine the composition of the electrolyte.
-->Following are the team’s observations.
“That’s when (the researchers) found that the polyethylene terephthalate, or PET, in the tape decomposes and creates the molecule that leads to the self-discharge. The molecule is called a redox shuttle because it can travel to the positive side of the electrode, then to the negative side and then back to the positive side. So, it shuttles between the electrodes and that creates the self-discharge, just like lithium is supposed to do. The problem is that the shuttle molecule is doing it all the time in the background, even when no lithium is supposed to move when the battery just sitting there.”
“It’s something we never expected because no one looks at these inactive components, these tapes and plastic foils in the battery cell but it really needs to be considered if you want to limit side reactions in the battery cell,” Dr. Metzger said.
Dr. Metzger and his team’s findings can be found below.
Buechele 2023 J. Electrochem. Soc. 170 010518 by Simon Alvarez on Scribd
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Tesla sees sharp November rebound in China as Model Y demand surges
New data from the China Passenger Car Association (CPCA) shows a 9.95% year-on-year increase and a 40.98% jump month-over-month.
Tesla’s sales momentum in China strengthened in November, with wholesale volumes rising to 86,700 units, reversing a slowdown seen in October.
New data from the China Passenger Car Association (CPCA) shows a 9.95% year-on-year increase and a 40.98% jump month-over-month. This was partly driven by tightened delivery windows, targeted marketing, and buyers moving to secure vehicles before changes to national purchase tax incentives take effect.
Tesla’s November rebound coincided with a noticeable spike in Model Y interest across China. Delivery wait times extended multiple times over the month, jumping from an initial 2–5 weeks to estimated handovers in January and February 2026 for most five-seat variants. Only the six-seat Model Y L kept its 4–8 week estimated delivery timeframe.
The company amplified these delivery updates across its Chinese social media channels, urging buyers to lock in orders early to secure 2025 delivery slots and preserve eligibility for current purchase tax incentives, as noted in a CNEV Post report. Tesla also highlighted that new inventory-built Model Y units were available for customers seeking guaranteed handovers before December 31.
This combination of urgency marketing and genuine supply-demand pressure seemed to have helped boost November’s volumes, stabilizing what had been a year marked by several months of year-over-year declines.
-->For the January–November period, Tesla China recorded 754,561 wholesale units, an 8.30% decline compared to the same period last year. The company’s Shanghai Gigafactory continues to operate as both a domestic production base and a major global export hub, building the Model 3 and Model Y for markets across Asia, Europe, and the Middle East, among other territories.
Tesla bear Michael Burry got blunt with his beliefs over the company’s valuation, which he called “ridiculously overvalued” in a newsletter to subscribers this past weekend.
“Tesla’s market capitalization is ridiculously overvalued today and has been for a good long time,” Burry, who was the inspiration for the movie The Big Short, and was portrayed by Christian Bale.
Burry went on to say, “As an aside, the Elon cult was all-in on electric cars until competition showed up, then all-in on autonomous driving until competition showed up, and now is all-in on robots — until competition shows up.”
Tesla bear Michael Burry ditches bet against $TSLA, says ‘media inflated’ the situation
For a long time, Burry has been skeptical of Tesla, its stock, and its CEO, Elon Musk, even placing a $530 million bet against shares several years ago. Eventually, Burry’s short position extended to other supporters of the company, including ARK Invest.
Tesla has long drawn skepticism from investors and more traditional analysts, who believe its valuation is overblown. However, the company is not traded as a traditional stock, something that other Wall Street firms have recognized.
While many believe the company has some serious pull as an automaker, an identity that helped it reach the valuation it has, Tesla has more than transformed into a robotics, AI, and self-driving play, pulling itself into the realm of some of the most recognizable stocks in tech.
Burry’s Scion Asset Management has put its money where its mouth is against Tesla stock on several occasions, but the firm has not yielded positive results, as shares have increased in value since 2020 by over 115 percent. The firm closed in May.
In 2020, it launched its short position, but by October 2021, it had ditched that position.
Tesla has had a tumultuous year on Wall Street, dipping significantly to around the $220 mark at one point. However, it rebounded significantly in September, climbing back up to the $400 region, as it currently trades at around $430.
It closed at $430.14 on Monday.
Tesla appears to be making a change to its exterior side repeater cameras, which are used for the company’s Full Self-Driving suite, and other features, like Sentry Mode.
The change appears to be a potential upgrade in preparation for the AI5 suite, which CEO Elon Musk said will be present on a handful of vehicles next year, but will not be widely implemented until 2027.
Currently, Tesla uses a Sony sensor lens with the model number IMX963, a 5-megapixel camera with better dynamic range and low-light performance over the past iteration in Hardware 3 vehicles. Cameras in HW3 cars were only 1.2 megapixels.
However, Tesla is looking to upgrade, it appears, as Tesla hacker greentheonly has spotted a new sensor model in its firmware code, with the model number IMX00N being explicitly mentioned:
Looks like Tesla is changing (upgrading?) cameras in (some?) new cars produced.
Where as HW4 to date used exterior cameras with IMX963, now they (might potentially) have something called IMX00N— green (@greentheonly) December 1, 2025
Sony has not announced any formal specifications for the IMX00N model, and although IMX963 has been used in AI4/HW4 vehicles, it only makes sense that Tesla would prepare to upgrade these external cameras once again in preparation for what it believes to be the second hardware iteration capable of fully autonomous self-driving.
Tesla has maintained that AI4/HW4 vehicles are capable of self-driving operation, but AI5 will likely help the company make significant strides, especially in terms of overall performance and data collection.
Tesla last updated its exterior cameras on its vehicles back in early 2023, as it transitioned to the 5-megapixel IMX963. It also added additional cameras to its vehicles in January with the new Model Y, which featured an additional lens on the front bumper to help with Full Self-Driving.
Tesla’s new self-driving computer (HW4): more cameras, radar, and more
Tesla sees sharp November rebound in China as Model Y demand surges
Tesla bear gets blunt with beliefs over company valuation
