iTECH400X PRO 12v 400Ah Lithium Battery

Regular price $5,000 Sale price $2,999 Save $2,001
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*Out of stock. Dispatch or pickup mid May*

Quick facts about the iTECH400X PRO 12v 400Ah Lithium Battery:

  • True drop-in replacement - no need to change chargers or equipment
  • Will fit in the space of your old 200Ah batteries
  • IP67 Waterproof - perfect for external mounting
  • Only weighs 38 kg (Equivalent AGM weighs approx. 240kg)
  • 400Ah of 100% usable capacity
  • 5-year Australian warranty 
  • Australian designed and developed
  • Australian certified including IEC:62619

After years of design and development spanning from the inception of iTechworld in 2006, we are proud to introduce the all-new iTECH400X PRO 400Ah 12v Lithium Battery.

As one of the most powerful 12v lithium batteries in Australia today, the iTECH400X PRO was designed with Australia’s harsh climate in mind which is why this iTECH400X PRO is IP67 waterproof, suitable for high heat conditions, vibration proof, certified to IEC 62619 and backed by a 5 year Aussie warranty.  

Thanks to our extremely high-quality A-grade prismatic lithium LiFePO4 cells, we have been able to shrink the size of the iTECH400X PRO to the same size as many standard AGM 200Ah battery packs while having the equivalent useable power as four (4) of them combined.  

With its compact design, the iTECH400X PRO is a true drop-in replacement for your existing system. No changing of systems, chargers, or equipment is required in most cases. Simply pull out your old AGM or flooded lead-acid battery and drop in the iTECH400X PRO. It's that easy! 

The iTECH400X PRO features a fully 100% useable capacity, allowing the full 400Ah to be drawn from the battery. The iTECH400X PRO includes an all-new patent-pending prismatic cell type, as well as an all-new supercharged Battery Management System (BMS) allowing for less cell degradation, safe and accurate operation, and a longer lifespan with high current use. With a maximum continuous discharge current of 200Ah, these batteries outperform many competitors.

Frequently asked questions about 400Ah lithium 12v batteries

1. How long will a 400Ah lithium battery last (how many hours)?

A 400Ah lithium 12-volt battery can last an extended period, providing continuous power for various devices. Unlike AGM batteries, which typically have a lower usable capacity, lithium batteries utilise 100% of their power capacity.

This means you can rely on the full 400Ah to power your devices, ensuring longer runtimes and enhanced performance.

2. How much solar (number of solar panels) do you need to charge a 400Ah lithium 12v battery?

To charge a 400Ah lithium deep cycle battery effectively, we recommend a 2:1 ratio of solar panels to battery capacity. In this case, for every 400Ah battery, we suggest using approximately 800 watts of solar power.

Our range of solar panels, including 150-watt hard frame panels, 200-watt flexi panels, and 300-watt solar blankets, offers versatile options to meet your charging needs efficiently.

3. What size charger is best for a 400Ah lithium battery?

For charging a 400Ah lithium battery, we recommend using either the iTECHBC40 40-amp AC charger or the iTECHDCDC40 40-amp DC charger. These chargers are designed to provide fast and reliable charging, ensuring your battery is replenished quickly and efficiently.

4. What can a 400Ah lithium battery power?

A 400Ah lithium 12v battery offers ample power to run various devices and appliances, making it ideal for off-grid and mobile applications. With its large capacity and high energy density, it can power a 12V fridge for weeks.

Additionally, it has enough usable capacity to support a significant inverter, allowing you to run AC appliances such as a coffee machine, air fryer, toaster, kettle, induction hot plates and everything in between.

The iTECH400X PRO could power a modern caravan air conditioner via an inverter for extended periods, typically exceeding 10 hours of runtime.

Built for the tough Australian environment, the iTECH400X PRO is IP67 Waterproof rated, allowing the battery to be submerged under one (1) metre of water for up to 30 minutes - perfect for marine applications or outdoor storage boxes. The iTECH400X PRO utilises the latest prismatic cell design offering more vibration resistance and stability for big bumps with vibration-dampening technology. 

After almost 20 years of extensive design, development, and testing, we are proud to present the 2024 iTECH400X PRO as our new flagship battery, backed by an extensive 5-year Australian Warranty. Upgrade to the iTECH400X PRO today and experience the ultimate in power and performance. 

Package contents of the iTECH400X PRO

  • 1x iTECH240X PRO 400Ah Lithium 12v Battery 
  • 1x Instruction Manual (Digital version  HERE) 

Warranty & Support

The iTECH400X PRO warranty is 5 years (3 years full replacement 2 years pro-rata).

*Storage deep cycle battery only. It cannot be used as a cranking battery.

If your iTechworld battery enters safe mode, please follow the instructions HERE


Nominal Voltage:  12.8V
C20 Rating usable amps 10v: 400Ah
Short Circuit Protection: Yes
Optimum Temperature Range: +5 to +60°C
BMS Operational Temperature Range: -5 to 80°C
Safety Protection Isolator: 80°C
Recommended Charge Current: 1 - 100A
Maximum Charge Current: 200A 
Recommended Charge Voltage: 14.4V
BMS Charge Cut Off Voltage: 15V
BMS Low Voltage Cut Off: 8.5 - 9V
Continuous Discharge: 250A 
Peak Discharge: 500A (5 secs)
Series Connection: Up to 48V (4 x batteries)
Parallel Connection: Unlimited
Life Cycles 100%: 4000
Life Cycles 50%: 8000+
Dimensions (LxWxH): 525x240x220mm (235mm including terminals) 
Weight: 38Kg
Terminal Type: M8
Case Material: ABS
UL Certified 1642
CE Certified
IP67 Rated
Rohs Certified
UN38.3 Certified
ISO 9001 Certified
ISO 1400 Certified