SAJ Battery
Review (2025)
Last updated: 23 July 2025
Table of Contents
- 1. A Budget Battery with Trade-Offs Worth Understanding
- 2. Quick Pros & Cons
- 3. SAJ Battery Performance Matrix (2025)
- 4. Is the SAJ Battery Right for You?
- 5. About SAJ
- 6. SAJ Battery Model Range
- 7. Key Specifications
- 8. Expanded Pros & Cons
- 9. Installation, Support and Warranty
- 10. Smart Monitoring and App
- 11. Ask Us Anything
- 12. Downloadable Documents
- 13. Final Verdict: Should You Buy a SAJ Battery in 2025?
A Budget Battery with Trade-Offs Worth Understanding
If you’re researching solar batteries in Australia, you may come across SAJ, particularly when considering a system that includes a SAJ inverter. The company’s modular B2 battery range is approved by the Clean Energy Council, supports up to 25 kilowatt-hours of scalable storage, and qualifies for current federal and state-based battery rebates.
Â
SAJ’s system offers some practical features. It includes outdoor-rated enclosures, stackable capacity options, and relatively low pricing. However, there are important limitations to be aware of. The brand is still emerging in the Australian market, its support presence is limited, and its battery app experience does not match more established competitors. Warranty terms are also less clearly defined than those offered by top-tier brands.
Â
This review explains what you need to know before choosing SAJ. We look at whether it suits your home, how it compares to other options, and what to expect in terms of performance, support, and long-term value.
Quick Pros & Cons
What Stands Out About the SAJ
B2 Battery System
Pros
- Modular design allows storage from 5 to 25 kilowatt-hours
- Outdoor-rated (IP65) and suitable for Australian conditions
- Compatible with SAJ hybrid inverters for seamless pairing
- 95 percent depth of discharge offers high usable capacity
- Eligible for federal and state battery rebates
- Remote firmware updates and basic energy monitoring app
Cons
- Limited brand presence and support network in Australia
- App interface and monitoring features are basic
- Warranty terms lack detail on cycle coverage and throughput
- Most effective when paired with a SAJ inverter
- Not widely recommended by Tier 1 installers
SAJ Battery Performance Matrix (2025)
Technical Performance
User Experience
Trust & Support
Overall Score
64%
64%
Best suited to homeowners seeking a low-cost battery solution that pairs with SAJ inverters, but who are comfortable with limited brand visibility, basic app features, and less proven long-term support.
Is the SAJ Battery Right for You?
The SAJ battery is a practical option for homeowners who want a scalable storage system that pairs neatly with a SAJ hybrid inverter. If you’re already using SAJ for your solar system, or plan to install one of their inverters, this battery offers a simple and affordable way to add energy storage. It’s outdoor-rated, stackable up to 25 kilowatt-hours, and approved for Australian battery rebate programs.
Â
However, it’s important to understand the trade-offs. The monitoring app is limited compared to more advanced systems. Warranty documentation lacks transparency on cycle throughput and degradation, and support channels within Australia are still developing. You may also find fewer local installers with hands-on experience servicing SAJ batteries.
Â
This battery is most suitable for price-conscious buyers who value integration over premium features, and who are happy to accept a basic software experience in exchange for a lower upfront cost.
About SAJ
SAJ, officially known as Guangzhou Sanjing Electric Co Ltd, is a Chinese manufacturer specialising in solar inverters, battery storage systems, and energy management solutions. The company has been operating since 2005 and has deployed millions of inverter units globally, particularly in Europe, Asia, and South America.
Â
In Australia, SAJ is best known for its H2 hybrid inverter range, which is often used in budget solar packages. Its residential battery offering the B2 series is designed to integrate directly with SAJ hybrid inverters, offering a vertically aligned solution for solar and storage.
Â
While SAJ is recognized in some international markets, its brand presence in Australia remains limited, and it does not yet have a widespread installer or service network. For homeowners considering SAJ, this means that product availability, support, and warranty servicing may vary depending on your installer and region.
SAJ Battery Model Range
The SAJ B2 series is a modular, high-voltage lithium battery system designed for residential use. It is available in five main capacities, each built by stacking 5 kilowatt-hour battery modules. The system is approved by the Clean Energy Council in Australia and can be installed either on the wall or ground, with IP65 protection for outdoor use.
SAJ B2 Battery Models (Residential)
| Model | Nominal Capacity | Usable Capacity | No. of Modules |
|---|---|---|---|
| B2-5.0-HV1 / HV5 | 5.0 kWh | 4.5 kWh | 1 |
| B2-10.0-HV1 / HV5 | 10.0 kWh | 9.0 kWh | 2 |
| B2-15.0-HV1 / HV5 | 15.0 kWh | 13.5 kWh | 3 |
| B2-20.0-HV1 / HV5 | 20.0 kWh | 18.0 kWh | 4 |
| B2-25.0-HV1 / HV5 | 25.0 kWh | 22.5 kWh | 5 |
These batteries are typically paired with SAJ’s H2 hybrid inverters for maximum compatibility. Each module weighs just over 50 kilograms, and the system can be configured to suit single or three-phase setups depending on the inverter used.
Commercial and Large-Scale Options
SAJ also offers the CHS2 series for commercial and high-demand residential use, with pre-assembled systems ranging from 51 to over 180 kilowatt-hours. These models are also CEC-approved and come with integrated inverters.
Key Specifications
The SAJ B2 battery system is designed with flexibility and simplicity in mind. Each unit is built around stackable 5 kilowatt-hour modules, with support for up to five modules per system. The system includes a control unit, offers high-voltage operation, and is rated for both wall and ground installation.
SAJ B2 Battery Specs
- Usable Capacity: 4.5 to 22.5 kWh (95% depth of discharge)
- Battery Chemistry: Lithium-ion (LFP)
- Nominal Voltage: 102.4 V per module (scales up with more modules)
- Operating Voltage Range: 89.6 V to 576.0 V (model dependent)
- Max Charge/Discharge Current: 30 A
- Installation: Wall-mounted or floor-mounted
- Ingress Protection: IP65 (suitable for outdoor use)
- Cooling: Natural convection
- Operating Temperature: -10°C to 50°C
- Communication: CAN protocol
- Warranty: 5 or 10 years (based on installer agreement)
The system supports remote firmware updates and basic app-based monitoring via the SAJ platform. However, data granularity and user experience are more limited than with premium brands.
Expanded Pros & Cons
A deeper look at the strengths and weaknesses of the SAJ B2 battery reveals a system that performs well on basic functionality and affordability, but with notable gaps in support and refinement.
Strengths
- Flexible Storage Capacity
The B2 system offers a wide range of sizes, from 5 to 25 kilowatt-hours, making it suitable for everything from small homes with solar time-shifting needs to larger households seeking partial backup.
- Outdoor-Ready Design
With an IP65 rating and natural convection cooling, the battery can be safely installed outdoors in most Australian climates without additional enclosures.
- High Usable Capacity
Each module provides 95 percent depth of discharge, delivering more usable energy than many lower-end systems.
- Good Value for Money
Pricing is generally competitive, especially when paired with a SAJ inverter. For budget-conscious buyers, this system offers significant storage capacity at a lower upfront cost.
- CEC-Approved and Rebate Eligible
The battery is included on the Clean Energy Council list, which means it qualifies for federal and state-based rebates, including the $372 per kilowatt-hour federal incentive.
Limitations
- Low Brand Recognition and Support
SAJ has minimal brand presence in Australia, and few installers list it as a preferred product. Post-sale support, spare parts, and service processes may be slower or less predictable.
- Basic App and Monitoring Tools
The SAJ battery app offers essential functionality, but it lacks the polish and real-time performance insights found in systems like Tesla, Enphase, or Sungrow.
- Limited Backup Capability
The battery is compatible with backup operation when used with the correct SAJ hybrid inverter, but the switching time and configuration options are limited compared to systems designed for whole-home backup.
- Unclear Warranty Terms
While SAJ promotes a 10-year warranty, there is little publicly available detail around cycle throughput, degradation expectations, or claim processes in Australia.
- Best Used With SAJ Inverters
Although technically a standalone battery, the B2 system performs best when paired with a SAJ inverter. Compatibility with third-party brands is limited and not widely supported.
Installation, Support and Warranty
Installation
The SAJ B2 battery system is designed for streamlined installation, particularly when used with SAJ hybrid inverters. Its modular design allows flexible sizing from 5 to 25 kilowatt-hours, and installation can be wall-mounted or ground-mounted. Each module weighs around 50 kilograms, so safe handling requires a two-person lift.
Â
While the hardware is straightforward, installation quality depends on the experience of your installer. It’s best to choose an installer who is familiar with SAJ systems, particularly for inverter communication and system configuration.
Support
SAJ provides local support through its Australian office, giving installers and end-users access to technical assistance, firmware updates, and warranty claims management. This improves service reliability compared to offshore-only manufacturers and makes SAJ more viable for homeowners who value local backup when issues arise.
Â
That said, because SAJ is still gaining recognition in Australia, not all installers are familiar with the platform, and support responsiveness can still vary depending on the installation partner.
Warranty
The B2 battery system comes with a 10-year product warranty, though detailed public information on cycle life and throughput limits is limited. Homeowners are encouraged to confirm warranty specifics with their installer and request documentation outlining performance guarantees over time.
Â
While SAJ does offer warranty coverage in Australia, the clarity and transparency of those terms are not yet at the same level as top-tier brands like Tesla or BYD, which publish detailed cycle and throughput expectations.
Smart Monitoring and App
The SAJ battery system includes remote monitoring through the SAJ Smart App, which also supports inverter communication and system updates. The app provides basic insights into battery charge level, solar generation, consumption, and grid export or import.
What the App Does Well:
- Shows real-time battery status and daily energy flows
- Enables remote firmware upgrades when connected to the internet
- Integrates inverter and battery data in one platform (when using SAJ hybrid inverters)
Where It Falls Short:
- User interface is basic and not as intuitive as platforms from Tesla, SolarEdge, or Enphase
- Graphs and data reporting are limited in depth and can be difficult to interpret for some users
- Customization is minimal there is limited control over charge/discharge timing or backup prioritization
The app is functional enough for basic system monitoring but may leave more tech-savvy users wanting more detail and flexibility. For households where smart control and in-depth energy reporting are priorities, SAJ may not be the best fit.
We Have Great Answers
Ask Us Anything
SAJ batteries offer good value for money and are suitable for homeowners looking for a budget-friendly solution that integrates well with SAJ inverters. However, they are less established than premium brands and may lack the long-term performance data, app quality, and warranty clarity found in more widely used systems.
SAJ batteries are manufactured by Guangzhou Sanjing Electric Co Ltd, based in China. The company has been producing solar energy equipment since 2005 and exports to markets across Europe, Asia, and South America.
The B2 battery comes with a 10-year product warranty. However, specific details around cycle life, throughput, and performance guarantees are not as clearly documented as those from leading brands. It’s best to request a written warranty from your installer.
Prices vary depending on the system size and installer. As a general guide, the installed cost of a 10 kilowatt-hour SAJ battery system typically falls between $8,000 and $10,000 before rebates. Larger systems (20 to 25 kWh) offer better value per kilowatt-hour but will cost more overall. Always confirm with your local installer.
The B2 battery is technically high-voltage and may be compatible with some other inverter brands using CAN communication, but it is primarily designed to work with SAJ hybrid inverters. Compatibility with other systems is not widely supported, so pairing with SAJ hardware is strongly recommended.
The SAJ Smart App provides basic monitoring of battery charge, energy flows, and system status. It’s functional but lacks the detailed insights, control options, and user interface polish offered by apps from Tesla, Enphase, or SolarEdge.
The B2 battery is designed to operate for 10 years under standard residential use. However, long-term data on cycle performance in Australian conditions is limited. Battery life may vary depending on usage patterns, temperature exposure, and installation quality.
Downloadable Documents
Technical specifications including dimensions, voltage, capacity, and environmental ratings.
Outlines warranty duration, coverage conditions, and key exclusions
Installer guide covering system wiring, safety requirements, inverter pairing, and commissioning steps.
If your installer hasn’t provided these, feel free to request them from us or directly through SAJ’s Australian office.
Final Verdict: Should You Buy a SAJ Battery in 2025?
The SAJ B2 battery is a cost-effective, modular storage system that integrates neatly with SAJ’s own hybrid inverters. It offers usable capacity from 4.5 to 22.5 kilowatt-hours, is approved for rebates in Australia, and includes practical features like outdoor installation, stackable design, and remote firmware upgrades.
However, it also comes with real trade-offs. The app interface is basic, warranty documentation lacks clarity, and brand support while improving with a local office still trails behind more established competitors. Most importantly, long-term performance data is limited, which makes it harder to assess how the system will hold up over time.
Â
If you are already using a SAJ inverter and want a budget battery to match, this system may suit your needs. But for homeowners who prioritize app quality, proven support, or want to mix and match brands, there are stronger options available above this price tier.
Overall Score: 64%
This battery falls below our recommended threshold. It may still suit budget-conscious homeowners seeking a simple, rebate-eligible battery with SAJ system compatibility, but it comes with notable trade-offs in support, transparency, and monitoring.
