iStore solar inverters and batteries - Updated October 16th 2024

iStore is a 12 year old Australian brand of electric heat pump hot water systems, and now solar inverters and batteries.


iStore solar products are manufactured by Huawei under an OEM agreement with iStore for the Australian/New Zealand markets.
Huawei have been the World's largest manufacturer Worldwide of solar inverters for the last six years.
They had a crack at selling into the Australian market direct, but eventually handed their product range over to iStore.
In my opinion this has proven to be mostly a good thing.
Brand recognition for the Huawei name meant selling them was often easy, but that brand name also carried some negative perceptions too.

Compatibility between iStore and Huawei products.
Those who bought Huawei hybrid L1, M0 and M1 5kW and 6kW single and three phase inverters can add an iStore battery to their system.
They can choose to stay on Huawei's Fusionsolar reporting platform or migrate to iStore Univers EMS platform.

iStore inverter range.
Single phase, 5kW, 6kW and 10kW hybrid inverters (compatible with iStore's batteries)
Three phase, 5kW, 6kW, 10kW, 15kW and 25kW hybrid inverters (compatible with iStore's batteries)

iStore single phase hybrid brochure.
iStore 5 & 6kW three phase hybrid brochure.
iStore 10/15/20/25kW three phase hybrid brochure.

iStore oversizing with a battery
250% oversizing is allowed with all iStore hybrid inverters with a battery.
That means...
12.5kW of panels with a 5kW inverter
25kW of panels with a 10kW inverter
37.5kW of panels with a 15kW inverter
62.5kW of panels with a 25kW inverter

23 x 440W panels to a 1000V string = 10.12kW per string.
Put 2 strings in parallel on an MPPT = 20.24kW
Double that for the second MPPT = 40.48kW of panels.

So therefore iStore's datasheet showing the 25kW inverter can have up to 62.5kW of panels isn't actually possible,
but seeing as we aren't allowed anything larger than 15kW in WA, then it's 37.5kW oversize is doable.

iStore battery.
This is probably the best battery on the market from an established player.
Each 5kWh battery module is independent of every other 5kWh module in the stack.
It can be charged, discharged, and most importantly, cell-balanced, individually.
The modules are parallel connected, not series, and have a battery optimiser inside.
While other batteries struggle to adequately balance cells in a big stack of series connected batteries,
the iStore battery system can work on cell balancing one smaller module at a time.
The cells are LFP (Lithium Iron Phosphate), the current safest chemistry.
With most LFP batteries having an effective 4,500 cycles, it's likely that the design of this battery should yield 6,000+ cycles.
There is a larger iStore battery coming in 2025 intended for the big 3 phase hybrids that reportedly will have a warranted 12,000 cycles.
Same optimised, parallel-connected design.


The battery is made up of 3 x 5kWh modules per stack with 2 x stacks possible per inverter.
The stacks don't have to be even, again, because each module is independently controlled.
A 5kWh battery on it's own has a charge/discharge rate of 2.5kW, but anything larger is 5kW.
My recommendations for multiple stacks, based on experience are...
2 x 10kWh stacks or 15kWh stack 1 plus 10kWh stack 2, or 15kWh both stacks.
Don't have a 5kWh stack and a 15kWh stack as they will have different charge/discharge rates.

Each 5kWh battery module includes 8 x temperature sensors and a self-deploying fire extinguishing bag.
Thermal runaway is virtually unheard of with LFP batteries, but a very nice bit of peace of mind tech anyway.

iStore battery brochure.

iStore reporting
iStore have developed their own installer and user apps.
Univers EMS, the user app certainly seems to be fit for purpose.
I get the feeling that there is plenty more to come though.
It's less than a year old.
The Home Assistant experts may get there first though...they usually do :-)

Smart energy management due 2025.
Weather forecast based automatic battery charging from grid at off-peak rates.
Direct surplus PV power to iStore smart EV charger, or turn on loads (e.g. hot water, pumps, A/C).

iStore smart EV Charger coming 2025...maybe?
There are so many EV Chargers on the market already it's hard to see much of a case for yet another.
3rd party products like Zappi are able to monitor solar production and only charge from available solar.
I think that having inverter control via the inverter consumption meter may well work a bit better though.
Huawei have made the smart chargers, it's up to whether iStore will bring them in.

iStore seem to have ignored Huawei's optimisers.
I'm not across why, but it certainly seems like iStore aren't going to support their own DC optimisers.
Huawei had them when they were selling direct in Australia, in fact my house has a string of nine Huawei optimised panels.
It's true that we never sold many, just a sprinkle here and there where people sometimes had shade on some panels.
Tigo optimisers as used by everyone else can do that job.
The great thing about Huawei optimisers though was that their reporting was built-into their app so you could see it all working.
Anyway, iStore seem to have decided they are not worth the trouble, so Tigo it is when there is shade.
Tigo also has reporting on each optimiser, but you have to buy a quite expensive add-on called Cloud Connect.

Warranty and support from iStore.
It's really nice to be dealing with Australians, in Australia, for support.
Even better is that they have a support team here in Perth.
Better still, that support team are active, and go out and about to help.
We recently had two new installs where the install teams couldn't get Wi-Fi to connect.
It's not an uncommon problem with any solar inverter as home router/modems can be fickle.
Usually my job to fix, I was in Europe not due back for over a week,
so iStore sent one of their support team out to fix the problem.
No charge, no fuss, they volunteered to help, drove out, and fixed it.
I have to say, that is not typical of the support provided by other brands.

Would I recommend iStore inverters and batteries
Without any hesitation.
For those buying a small 5kW/6kW inverter that can connect a battery now or later, it's very well priced.
Buying 2x or even 3x of these smaller inverters that work brilliantly in Master-Slave is a cost effective option,
when considering a 10kW-15kW three phase installation with batteries.

The battery is, as described above, the most efficient and probably safest on the market, bar perhaps Sigenergy's.
Support is local and excellent, the app is already good enough, and getting better.
They are a 12+ year old Australian success story.
Can't count how many times I have heard'...
"I love my iStore hot water heat pump, so I'm happy to get their solar products as well".
Whilst the fact that Huawei make the products is hidden, it's actually proof of how good the products are under the hood.

When the larger 3 phase inverters come on stream, hopefully by the end of 2024, it will be a complete product range.
iStore installation manual.

(08) 9467 9655

or email

This review was written by Andrew MacKeith, Solar4Ever service manager since 2011.
Solar4Ever is located in Morley (Perth), WA 6062