This report provides analysis and discussion of the process of installing the batteries and testing data collected for March 2017.
Report extract
ITP Renewables (ITP) are testing the performance of commercially available residential or small commercial scale lithium-ion batteries. The aim of the testing is to independently verify battery performance against manufacturers’ claims. Specifically, ITP is investigating capacity fade, efficiency, and charge characteristics of six lithium-ion batteries, one conventional lead-acid battery, and one advanced lead-acid battery. They are tested in a purpose-built climate-controlled enclosure at the Canberra Institute of Technology.
Battery cycling has now been ongoing since August 2016, and will continue until end July 2020. Capacity and efficiency tests have been conducted in each of the six months between September 2016 and February 2017. At this early stage, capacity fade is evident for some of the battery packs under test, but for others, the long term trend is difficult to discern, owing largely to the inherent variability of battery capacity between cycles.
Since testing has commenced, one of the lithium-ion battery packs has suffered irreversible damage due to improper low-voltage protection provided by the built-in Battery Management System (BMS). Another battery is functional but showing evidence of either a weak cell or poor battery management by the BMS.
While trends in capacity fade are expected to become clearer over the next six months of testing, already it can be seen that lithium-ion efficiency is generally higher than the conventional lead acid pack.
