This experiment is based on a user scenario in which a vehicle that is already out of warranty shows BMS a079 symptoms, and the owner tries to keep using the vehicle as stably as possible while accepting a certain level of inconvenience. This is the third-week result since the first detection of the BMS a079 phenomenon. So far, the BMS a079 error code has not actually occurred. In last week’s middle graph, the cell voltage deviation widened up to 0.09 V. Starting this week, h

These days, because of recent Tesla issues, many people say things like “using cylindrical cells was a mistake” or “Tesla had no choice but to use them.” That might have been true long ago when prismatic and pouch cells were not widely available. But even today, choosing a cell type is far from a simple decision. In battery pack design, there is always a trade-off. Safety, energy density, manufacturing complexity, and cost are all interconnected, and the outcome depends on wh

I recently came across a post on Reddit’s DrEVdev where someone cited an article claiming that Tesla Supercharging is not related to battery degradation. I will not specify the original source here. Collecting and analyzing such data is not an easy task, and I have no intention of criticizing the author. However, since the article has been widely referenced in blogs and YouTube videos, leading some people to believe that fast charging has no relation to battery degradation, I

Although we have analyzed numerous user datasets and real-world cases, this is the first time we have personally observed the same issue on our own vehicle. This gives us a valuable opportunity to study the problem not only from the developer’s perspective but also as an actual owner experiencing it firsthand. To share some background: the vehicle was purchased used in June of last year with about 120,000 km. It has mainly been used for development, and the annual mileage is