I have added the second 10 KWh string to my setup by the beginning of April 2018.
This string is made of 980 X Panasonic NCR18650PF's cells. You can see them in the foreground (the green cells).
The first string, made of various types of cells, sits behind. The complete battery is a 140P14S stack (1960 cells in total).
The long rods are tinned copper bus bars which insure the parallelization of the modules. As they are quite long, there is provision for addition of two more strings.
I have also added an LCD display that indicates Battery voltage, current and temperature as well as input / output powers.
Battery management is performed by my wireless modular BMS
This battery pack covers now 2 days of consumption. A third string is planned for addition this summer.