Solar Energy Storage Systems Project with 11kW Battery Inverter and 33 kWh LiFePO4 Storage Battery

In today’s energy landscape, many homeowners and small businesses choose solar energy storage to cut costs, improve resilience, and reduce grid dependence. This case study describes a project that uses 2 Axpert MAX TWIN off-grid inverters and 2 M90 PRO lithium battery modules to deliver reliable, efficient backup power.

Project Overview

• Inverters Installed: 2 × Axpert MAX TWIN (off-grid)
• Batteries Installed: 2 × M90 PRO lithium storage modules
• Total Battery Storage Capacity: 32.7 kWh (16.384 kWh × 2)
• Expected Lifespan: ≥ 8000 cycles @ 80% DOD
• Application: Residential energy storage and backup power

Axpert MAX TWIN Highlights

• Dual outputs for smart load management and scheduled secondary output
• 150A MPPT solar charger with wide PV input (90VDC–450VDC)
• RGB status LED bar and built-in Wi‑Fi for mobile monitoring (Android/iOS)
• Replaceable fan, parallel operation up to 6 units, and reserved BMS ports (RS485/CAN/RS232)
• Selectable high-power charging current and anti-dust kit

M90 PRO Battery Highlights

• Nominal Voltage: 51.2V | Capacity: 320Ah (16.384 kWh)
• Cycle Life: ≥ 8000 cycles @ 80% DOD
• Max Charge/Discharge Current: 200A
• Compact (990×505×200mm), lightweight (126.6 kg), and certified (ISO/UL/IEC/CE/UN38.3)
• Intelligent BMS, remote monitoring via inverter app, and >96% round‑trip efficiency

Practical Benefits

• Energy independence: Reduces reliance on unreliable grids and improves resilience during outages.
• Cost savings: Store daytime solar energy to avoid evening peak tariffs.
• Reliability: Dual inverters and multiple battery modules provide redundancy for critical loads.
• Longevity: High cycle life and efficient operation lower total cost of ownership over time.

Installation Notes

To maximize system performance, balance PV array sizing with inverter MPPT range (90V–450V) and set smart load priorities in the Axpert MAX TWIN. Configure the second output for non‑critical loads with scheduled on/off or SOC cut‑off to extend battery availability for critical circuits.

Market Insight

Residential energy storage adoption continues to grow as battery costs fall and incentives expand. Systems that combine modern inverters (with monitoring and smart load control) and long‑life lithium batteries deliver the best balance of performance, safety, and lifespan.

Conclusion

This case demonstrates a robust residential solution: 2 Axpert MAX TWIN battery inverterspaired with 2 M90 PRO batteries deliver about 33 kWh of usable storage, intelligent load management, and reliable backup. The design is scalable, future‑ready, and suitable for homeowners seeking resilience and long‑term savings.