Using solar chargers to harvest solar power

We are testing different solar chargers to see their performance with the LFP battery packs.  Here is the summary of our tests:

Figure 1 - shows the initial charging of a completely empty 48V/20AH LFP battery pack. We were able to charge 25Ah of power. We are using two 217Wp solar panels in series. They provide the peak of 350W.

Figure 2 - shows the discharge of the 48V/20AH LFP battery pack until the low voltage level of 44.4V is reached. The discharge with is a resistive load, so the current changes at the beginning and decreases as the heat spiral warms up.

Figure 3 - shows the charging mixed with periods of discharging.

Figure 4 - shows a complete discharge and charge cycle

Figure 5 – shows the detail of the charging cycle

The data are recorded using the PowerLog 6S device and processed by the http://www.logview.info/ software. You can download the data logs here VS1, VS2, VS3, VS4.