Delta Battery: An Independent Review by Solar Choice

delta battery

Background on Delta– Company History

You don’t hear a lot about Delta, but they produce some pretty solid solar gear. Delta has received dozens of internationally recognized design awards over the last decade or so, but they don’t do a lot in the way of marketing themselves.

Founded in the 1970’s and headquartered in Taiwan, Delta is probably better known for its inverter products, but it has also moved into battery storage.

Delta’s battery system, the Bx6.0 Li-Ion (part of the Deltra Hybrid E5 energy storage system), is protected by steel casing with four layered protection and is powered by Panasonic cells. Delta says as with all its products, it has been subject to extensive fire and impact testing.

The Delta Bx6.0 Li-Ion battery is backed by a 5 year warranty that can be extended to ten years. If you’re considering this battery, bear in mind it needs to be paired with a Delta inverter.

Over the last 50 years they have expanded into power electronics, industrial building automation and energy infrastructure projects. In 2019 the Delta Group posted an annual profit of AUD$1.1 billion, so they have a secure financial backing.

In 1999 Delta commenced the development of their first 260W grid-connect inverter for the German market. They now manufacture solar inverters from 2.5kW to 140kW and distribute across the world with local websites and offices set up in the USA, China, India, Japan, Korea, Thailand and Australia. Their Australian office is located in Notting Hill, Victoria.

Basics of  Delta Lithium Batteries

Delta BX 6.3AC

The Delta BX is their flagship battery with a usable capacity of 6.17kWh as per their datasheet. It can be integrated with a home PV system and can be scalable up to 12kWh for future expansion. With this battery, the house owner can maximize the efficiency of home energy management by saving and managing excess solar energy from the home PV system. Besides, it can also act as a source of backup power during emergency or suffering a power outage

They have a working temperature of -10 to 45 degrees Celsius which make them suitable to withstand the hot environmental extremes of Australia safely. On that point, they’re developed with lithium ion phosphate which is well known for their chemical safety with batteries, as well as providing a long cycle life.

Rated IP65 they’re designed to be used for both indoor and outdoor use which makes them versatile.

It’s compatible with  compliant inverters up to 5kw AC single phase. It’s not an all in one unit.  It includes an AC battery inverter but requires a solar inverter.

Delta Battery – Key Featuresdelta battery

There are a number of features of the Delta battery worth mentioning:

Scalable Capacity

As we’ve mentioned, these batteries are modular in design which enables you to connect them in parallel with a maximum of 2 units in order to scale the nominal capacity of your storage system. The advantage with this, is that it gives you the flexibility to expand your solar energy storage in the future. This may be useful if you’re finding that you’re finding your battery stretched with your night time use of appliances. This is achieved by a simple to use plug and play second DC coupled battery.

Smart App

Delta’s self-developed APP complements the product for easy monitoring by both customers and Delta. The benefit of this app is that it enables the user to both monitor and optimise their electricity consumption. Also, you can switch to charging up your battery system during off-peak tariff periods.

Charge from Grid or Solar

BX6.3 Series can harness your excess solar power to charge itself. For those without solar, charging from the grid during cheaper periods ensures maximum savings.

How Much Do Delta Batteries Cost?

We’ve reached out to Delta to find out the wholesale cost of their batteries. We’ll update this section once we hear back from them.

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Australian Warranty Terms for Delta Battery

As per Delta’s warranty documentation, Delta warrants that the product shall retain at least 50% of Nominal Energy (Minimum Nominal Energy) under normal use and service only, until whichever of the following is to first occur: a) 10 years from the date of first installation of the product; b) when the product exceeds energy throughput of 19.8MWh

There’s a few things about the warranty we think you should know:

  • If Delta elects to repair a product, it may, at its sole discretion, replace it with a comparable replacement product rather than the defective product being repaired. 
  • The customer must notify Delta of any warranty claims within seven (7) days of becoming aware of the product not achieving the Minimum Nominal Energy.
  •  If Delta is satisfied that the product cannot achieve the Minimum Nominal Energy within the warranty period, and the claim is made: a) within sixty (60) months from the date of first installation of the product, Delta shall provide the customer with a new replacement product. b) after sixty (60) months from the date of first installation of the product, Delta shall, at its sole discretion, repair the product or provide the customer with a comparable replacement product or a refund in accordance with the Refund Scheme

Warranty claims can be made By telephone to Delta’s Service Line on 1300 335 823 and describe the nature of the product failure.  By email to and provide a brief description of the product failure or complete and submit a replacement request on Delta’s service website:

Review Delta’ warranty document here.

BX6.3 Specifications

 BX BatteryBX Battery (2 x in parallel)
Usable Capacity6.17kWH12.34kWh
Typical VoltageDC 400 VDC 400 V
System Connection2
Battery ChemistryLi-ion
Operating Temp.-10°C to +45°C
Outdoor/Indoor(Both) IP65
Dimensions (W × H × D)570 × 830 × 250 mm1,140 × 830 × 250 mm
Weight80 kg160kg
Warranty10 years 

Read About Home Battery Government Schemes Across Australia

South Australia, New South Wales, Victoria, and Australian Capital Territory all currently have a home battery scheme in place.

The South Australian Home Battery Scheme enables eligible South Australian residents to receive up to $4,000 per installed battery.

The New South Wales Home Battery Scheme offers an interest-free loan up to $9000 for eligible households looking to install a solar battery.

The Victorian Government under the Solar Homes Program provides to those eligible, a maximum discount of $4,174 off the battery sale price. The next release of battery rebates is on the 2nd of September 2020.

The Australian Capital Territory Government under the Next Generation Energy Storage program provides a rebate of $825 per kilowatt (kW). An average household with a 5kW system would be eligible for approximately $4,000.

Read more product reviews from Solar Choice

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Since 2008 our knowledge and sophisticated software has allowed over 300,000 Australian households and businesses to make a well-informed choice on their solar & battery installer.
Jeff Sykes

Reviews from Australians who have installed Delta Batteries

Rated 5.00 from 2 reviews
25th April 2024
6kW system

6th April 2024
10kW system

A low cost battery with over 12kW of usable capacity. Yet still has functions and capabilities you see in the premium end of the industry.