The ARENA-funded ITP Battery Trial is pitting a long list of storage technologies against the elements. Which ones will make it and which will fizzle out? The ITP Renewables team sent this update from its Canberra laboratory.

In recent years there has been a surge in interest in battery storage in Australia, from residential to utility-scale. This has been driven by increasing electricity prices, improvements in battery performance, reductions in battery system costs, as well as state government subsidy schemes which support the uptake of home battery systems.

However, many end-users remain unsure about the performance of new battery technologies. Their track record is limited, and lab-based testing is rarely representative of the real-world conditions in which battery systems will operate.

The ITP battery trial

Enter the ARENA-funded ITP Battery Trial project, which started as a project designed to compare the performance of lithium-ion technology with lead-acid technology but has shifted towards providing guidance about the reliability and performance of a range of battery storage technologies on the market.

Designed, installed and operated by ITP Renewables, the battery trial cycles battery packs at an accelerated rate in ambient temperatures that reflect the daily temperature cycles across many Australian climates.

The test centre facility is located at the Canberra Institute of Technology (CIT). The first phase started mid-2016 and included eight batteries, with a further 10 batteries installed as part of phase two in mid-2017.

The batteries are mostly lithium ion, being either lithium iron phosphate (LFP) or nickel manganese cobalt (NMC) chemistry, but the team is also looking at lead-acid, lead-carbon, aqueous hybrid ion and zinc-bromine flow technologies.

Battery Trial Phase Manufacturing Location* Chemistry Installed Nominal Capacity (kWh)
CALB CA100 1 China Lithium Ion (LFP) 10.24
Ecoult UltraFlex 1 USA Lead Acid Carbon 14.8
GNB Sonnenschein Lead-Acid 1 Germany Lead Acid 15.84
Kokam Storaxe 1 Korea Lithium Ion (NMC) 8.3
LG Chem RESU 1 1 Korea Lithium Ion (NMC) 9.6
Samsung AIO10.8 1 Korea Lithium Ion (NMC) 11.6
Sony Fortelion 1 Japan Lithium Ion (LFP) 10.24
Tesla Powerwall 1 USA Lithium Ion (NMC) 10.24
Alpha ESS M48100 2 China Lithium Ion (LFP) 9.6
Ampetus Super Lithium 2 China Lithium Ion (LFP) 9
Aquion Aspen 2 USA Aqueous Hybrid Ion 17.6
BYD B-Box 2 China Lithium Ion (LFP) 10.2
GNB Sonnenschein Lithium 2 Germany Lithium Ion (NMC) 13.6
LG Chem RESU HV 2 Korea Lithium Ion (NMC) 9.8
Pylontech US2000B 2 China Lithium Ion (LFP) 9.6
Redflow ZCell 2 USA Zinc Bromine Flow 10
SimpliPhi PHI3.4 2 USA Lithium Ion (LFP) 10.2
Tesla Powerwall 2 2 USA Lithium Ion (NMC) 13.5

*At time of procurement

Information is collected and reported for each battery on: ease of installation; technical performance, including efficiency and capacity fade, and; operational performance, including any interruptions to cycling, faults, or required replacements.

The trial has provided results not only on the performance of individual batteries, but also the state of the battery storage market as a whole.

Key learnings, so far…

Battery storage is a rapidly evolving industry, with a large number of manufacturers entering (and some exiting) the market. Of the 18 batteries installed under the trial, one manufacturer and one distributor (selling re-branded Sinlion batteries) have become insolvent since the trial started (leaving us with batteries which are not properly cycling).

The reliability of the products, as well as the level of support available, varies widely, both for battery storage products and associated components (such as inverters).

The battery storage market is very much still developing, and with it, relevant standards and regulations. At the time of phase one installation in 2016, both the local distribution network and electrical installation regulatory service were generally unfamiliar with battery installations and did not have a standard approach. Regulatory requirements are now becoming clearer; there are now Australian standards being developed which include AS/NZS 5139 Electrical installations – Safety of battery systems for use with power conversion equipment and a battery performance standard for domestic/small commercial solar battery systems.

Many of the products on the market are new. For the trial, this resulted in a number of problems including product arrival delays, ambitious or inaccurate information on the compatibility of battery products with specific inverters (resulting in commissioning issues and delays) and installation difficulties when products arrived without all the necessary installation instructions or components.

The number of operational issues and failures experienced during the trial was much higher than expected, and a strong indicator of the state of the market. The chart on page five of the latest report gives an overview of battery operational performance throughout the trial.

To keep in mind…

Although the number of operational issues and failures has been higher than expected, ITP also notes that the batteries in the trial are being cycled three times per day, which is much more than might be expected for the typical solar-storage installation. This may have led to issues and failures which may not normally arise, particularly with regards to thermal management, as the batteries are given less time to rest and cool.

Also, due to practical considerations the trial only has one unit/system of each battery product installed. By doing this ITP is able to include a larger number of products, but it does mean that the results obtained for each product are not necessarily representative of the product in general.

The accelerated cycling was designed to enable analysis over a shorter timescale than a typical installation, but the battery market is rapidly evolving, and many manufacturers are constantly updating and improving their range. Although at the time of installation most batteries had only just entered the market, some of them are no longer the current model available.

More than a few positives

While there have been operational issues with most batteries, some batteries have performed very well in terms of reliability, efficiency and capacity retention. Both lead-acid and lithium-ion technologies have demonstrated round-trip efficiencies of 85-95%, and linear extrapolation of capacity retention to date suggests that lithium ion battery packs can generally deliver 2,000-6,000 equivalent full cycles before end-of-life.

Overall, the trial has shown that the lithium ion technology itself holds great potential, but that the industry is still working through product development, with a large variation in reliability and performance of available products.

ITP reports on the results of the battery trial in public reports released every six months at www.batterytestcentre.com.au, and has recently released Report 6. ITP hopes to expand its trial to include more products and technologies, which would allow it to continue sharing valuable information on battery products and the state of the storage market with potential end users.