Ecoult UltraFlex Indoor

UltraFLEX Indoor

The king of versatility

UltraFlex excels wherever there’s a need for high power and sustained energy.

It’s big enough to be serious – punching out 20 kW – but sized for pallet-jack delivery and able to find a spot on most sites.

Paired with a diesel generator, UltraFlex saves fuel. It charges and discharges quickly and continuously. The generator either doesn’t run at all, or runs beautifully at peak rated output. It can be given predictable operating conditions and decoupled from the load while the battery handles all the vagaries and fluctuations.

Self-contained and robust, UltraFlex can also be moved from site to site – it’s proven its worth by travelling from power-hungry building sites to music festivals that pump on, using the day’s solar energy long after sunset.

UltraFlex is fully and remotely monitored, so if you want to see how the site is running, just open your browser. Alerts are sent to you – and to us if necessary – to be acted on before they become problems.

Ecoult acknowledges the support and funding received from Australian Renewable Energy Agency (ARENA) under its “Emerging Renewables” and “Advancing Renewables” programs.

safe voltage


All UltraBattery products are fully flame retardant, comprise non-flammable components, and can provide high power at safe, extra-low voltages.

local support

Local Support

Trained installers are local to your site, and can log in from anywhere to check, diagnose, and respond remotely, or to schedule a visit.



Our systems are available to view and control from anywhere, with every battery individually monitored.

environment energy

Environmental Sustainability

We steward a truly sustainable, closed-loop technology that is helping to create a greener, lower-carbon energy system for the planet.

Power and Energy Data (4 x 48 V)

Continuous power rating* 1-hour rate 20.0 kW
Capacity for
regular cycling
10-hour rate 2.8 kW
Nominal capacity (100%) 28.2 kWh
Usable capacity
(60% range of charge)
16.9 kWh
Capacity for emergency
reserve events
Usable capacity
(90% range of charge
at 10‑hour rate)
25.4 kWh

*Charge rate tapered to a voltage limit at the top of the range of charge.

Cabinet Specifications

Nominal Voltage 48 V
Assembly Weight 1190 kg
Indoor UltraFlex Dimensions
(W x D x H)
1 x 0.6 x 2 m

Data subject to change without notice. Based on ambient temperature of 25° C.