One of our Dr.EV users recently asked us a common question: “Why is CB-R bad? And what can I actually do about it?” CB-R is a Dr.EV indicator designed to detect cell imbalance. Why cell imbalance is not good for your Tesla. When cells are imbalanced, the usable energy of the entire battery pack is limited by the weakest cell. In this case, we guide slow charging help passive cell balancing working well. Here is real graph. As SOC goes up, cell voltage differences usually get

The two charging graphs presented here are real data provided by a Korean user and a Chinese user who contacted us through the ‘Contact via Email’ feature in the Dr.EV app to inquire about their battery condition. All personal information has been removed, and only the necessary data has been used. First User (Left Graph) The user on the left performs almost all charging using DC fast charging.They frequently charge to 100 percent, and their daily charging routine also depend

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 continue using the car as stably as possible while accepting a certain level of inconvenience. It has now been five weeks since the BMS a079 phenomenon was first detected. So far, the BMS a079 error code has still never appeared. At around week 3, the battery condition worsened slightly. So, we limited the charging level to 60% and cap

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

This is the second week’s result since the first detection of the BMS a079 phenomenon last week. So far, the BMS a079 error code has not yet appeared. As shown in the left graph, even under the same charging conditions, the maximum cell deviation remains around 0.05 V, similar to last week. However, in the right graph, the maximum deviation has increased significantly to about 0.08 V. This difference is also clearly visible in the statistical data. While it’s possible to redu

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

Previously, you could only review data from your most recent session . Now, we’ve expanded the feature so you can analyze battery and...

Until now, Dr.EV only provided the “Personalized Remaining Life Distance,” which is calculated based on your actual driving and parking...

Tesla’s Sentry Mode is a popular security feature, but it has the drawback of draining the battery. Reports from Tesla owner communities...

Usable State of Charge (SOC) Definition:  Usable SOC  is the battery percentage that reflects the usable energy available for driving, as...

How Tesla Calculates Usable vs. Rated SOC and Range Estimates (Summary) 1. Usable State of Charge (SOC) Definition: Usable SOC shows the...

The motivation for this article on Tesla batteries arose from common user queries regarding the accuracy of SoH measurements based on...

As experienced BMS engineers and scientists, we have incorporated extensive expertise and research into creating the Dr.EV app,...

This guide outlines 10 common charging issues  faced during both AC (1–5)  and DC fast charging (6–10) , along with their causes and...

We introduced Tesla real-time charging monitoring after recognizing that many users experience issues such as charging compatibility...

Average predicted State of Health (SOH) for Tesla vehicles by model year, based on standardized odometer readings (10,000, 50,000,...

Vehicle and battery information NCM Model:  2020 / 118,030 km, SOH 83.1% LFP Model:  2022 / 121,104 km, SOH 93%   LFP (left), NCM...

The analysis presented above is an actual case demonstrating the advanced battery diagnostics and management recommendations provided by...

Initial range reduction is a natural phenomenon commonly observed in electric vehicles. Among Tesla owners, some have reported that the...