This report describes testing results and general observations or issues encountered thus far with both the Phase 1 and 2 battery pack testing.
ITP Renewables (ITP) are testing the performance of residential or small commercial-scale battery packs in a purpose-built climate-controlled enclosure at the Canberra Institute of Technology.
The first part of the report provides a review of the project to date covering the three previous report summaries. Report 1 covered the installation of Phase 1 batteries, including six lithium-ion, one conventional lead-acid, and one advanced lead-acid battery packs. Report 2 covered initial findings in the Phase 1 data.
Report 3 outlined the implementation of Phase 2 when the centre was expanded to include an additional eight lithium-ion packs, a zinc bromide flow battery, and a saltwater battery bank.
This report describes ongoing commissioning challenges with the Tesla Powerwall 2 and Aquion saltwater battery packs, the replacement of the Redflow and Ecoult packs, and upgrades to the Ampetus pack.
Ongoing erratic behaviour of the CALB lithium-ion and GNB lead-acid battery packs has been observed, but generally higher round-trip efficiency for lithium-ion technology over conventional lead-acid and zinc-bromide technologies has been demonstrated.
Capacity test results show characteristic capacity fade for all the Phase 1 battery packs (1,000+ cycles completed) still in operation. There is significant variability between packs, and the potential role of temperature effects in contributing to these results is discussed. Phase 2 battery packs (500+ cycles completed) show similar initial trends and variability in capacity fade. Longterm trends should be apparent in the next report.
The Battery Test Centre website is proving an effective means of knowledge sharing with page views of over 74,000, global reach and good interaction with the content.
Key lessons continue to be that manufacturer’s must comprehensively test their battery pack or battery management systems with the applicable inverter prior to dispatch.