I have 6x 2014 Tesla Model S battery modules in 2S3P config for 43.2V 630Ah configuration at roughly 85% state of health. They are charged by Victron MPPT 150/60 controller maxing out at 60A. I had Victron smart shunt logging battery data for 18 days and the result shows 98.9 % charge/discharge energy efficiency. Typical charge rate is 0.05 C and discharge rate 0.025 C or 20 hour charge and 40 hour discharge on average.
![tsla-batt-info.PNG tsla-batt-info.PNG](https://diysolarforum.com/data/attachments/152/152140-8972292e047ad4d7fef19b8b61ebe088.jpg)
Here is 18 days of voltage logging. Note that energy count was captured at exactly same 43.31 Volts and about the same load current of 5A or 0.008 C rate for the pack.
![tsla-batt-volt.PNG tsla-batt-volt.PNG](https://diysolarforum.com/data/attachments/152/152141-a5c0d0dcafa223cfc2414473124d422a.jpg)
Charge level estimate drifted down by 2% overtime. Still tweaking capacity and efficiency setting to minimize SOC drift.
![tesla-batt-soc.PNG tesla-batt-soc.PNG](https://diysolarforum.com/data/attachments/152/152142-4b2402300599eec042540223bef069f9.jpg)
.
![tsla-batt-info.PNG tsla-batt-info.PNG](https://diysolarforum.com/data/attachments/152/152140-8972292e047ad4d7fef19b8b61ebe088.jpg)
Here is 18 days of voltage logging. Note that energy count was captured at exactly same 43.31 Volts and about the same load current of 5A or 0.008 C rate for the pack.
![tsla-batt-volt.PNG tsla-batt-volt.PNG](https://diysolarforum.com/data/attachments/152/152141-a5c0d0dcafa223cfc2414473124d422a.jpg)
Charge level estimate drifted down by 2% overtime. Still tweaking capacity and efficiency setting to minimize SOC drift.
![tesla-batt-soc.PNG tesla-batt-soc.PNG](https://diysolarforum.com/data/attachments/152/152142-4b2402300599eec042540223bef069f9.jpg)
.