5.12kWh Solar Backup: Rubix 48V LiFePO4 Battery + 6.5kW Phocos Any-Grid Hybrid Inverter - ESS Kit

This kit includes the primary components listed below. Additional wiring, mounting hardware, or balance-of-system equipment may be required depending on your installation requirements. Contact our team for a personalized equipment review and custom add-on pricing.

The 5.12kWh Solar Backup: Rubix 48V LiFePO4 Battery 6.5kW Phocos Any-Grid Hybrid Inverter ESS Kit is a pre-matched solar battery backup system that pairs 5.12kWh of LiFePO4 storage with a 6,500W hybrid inverter — both confirmed compatible on voltage and charging current so you can skip the component-vetting process. Available through A1 SolarStore, it's sized for residential solar battery backup, off-grid cabins, and small commercial applications that need reliable, scalable energy storage without the compatibility risk of self-sourcing.

What's included

• Rubix RS51100 Stack Series Battery — 1× 51.2V / 100Ah (5.12kWh) LiFePO4 deep cycle battery module
• Phocos PSW-H-6.5KW-120/48V — 1× 6,500W single-phase hybrid solar inverter/charger
• Rubix Stack Series Base & Lid — 1× structural housing set for horizontal installation and future stack expansion

Component specifications

One purchase, zero compatibility risk

Pairing a 48V LiFePO4 battery with a hybrid inverter requires matching voltage range, max charging current, and cutoff thresholds — and getting any one of those wrong means returns, delays, or underperformance. This solar battery storage system bundles the RS51100 and PSW-H-6.5KW-120/48V as a pre-engineered pair: the inverter's 48V battery port and 120A max charge current are well within the Rubix battery's 70A continuous / 80A peak charge ratings, and both units carry RS485/CAN interfaces for setup and monitoring. Charge parameters are configured on the Phocos inverter at commissioning using Rubix's published voltage settings.

Who this kit fits

• Residential home backup — 5.12kWh covers lights, refrigeration, and essential appliances through a utility outage, delivered as clean 120Vac single-phase power.
• Off-grid cabin or workshop — pair with dual PV strings up to 5,000Wp each (10,000Wp total array) to run tools, lighting, and small HVAC loads independently of the grid.
• Whole house battery backup with solar — a starting point for homeowners who want to add storage to an existing PV system and scale capacity as energy needs grow.
• Small commercial or agricultural facility — reliable solar power backup for security systems, refrigeration, or critical equipment with a clear expansion path to 163.84kWh.
• Lead-acid replacements — buyers upgrading an aging 48V bank who want LiFePO4 longevity (4,500 cycles) without sourcing a matched inverter separately.

How the components work together

The Rubix RS51100 connects to the Phocos inverter's 48V battery terminals via M8 bolt-on lugs (torqued to 20 ft-lbs). The inverter charges the battery through its dual MPPT solar inputs — each accepting up to 5,000Wp at up to 250Vdc open-circuit voltage — and supplements charging from grid or generator at up to 120A. Charge parameters are set manually on the Phocos at commissioning using Rubix's published voltage thresholds; both units support RS485/CAN for monitoring and control. The Stack Series Base positions the battery horizontally, the required orientation per Rubix, and supports up to 5 additional RS51100 modules in the same physical stack for a single-stack total of 30.72kWh. Additional parallel stacks extend capacity further, up to 32 units and 163.84kWh system-wide, all fed through the same inverter. You will still need to source interconnecting DC cables, a DC fuse or breaker, an AC breaker for inverter output, and any conduit or mounting hardware required by your local installation code.

Why choose this ESS kit?

A1 SolarStore offers this kit because the RS51100 and PSW-H-6.5KW-120/48V are matched at the spec level — not just at the voltage label. The Rubix battery's UL 9540A certification addresses fire-safety compliance requirements common in permit-pull residential installations, while the Phocos inverter's UL1741 and CSA C22.2 No. 107.1-16 listings satisfy utility interconnection requirements across most US and Canadian jurisdictions. The 6,500W continuous output and 120A solar charge capacity give this kit a meaningful headroom advantage over 5kW alternatives — useful for installations with larger PV arrays or higher load demands. And because the Rubix Stack Series is designed around a modular base-and-lid housing, expanding storage later is a matter of adding modules — not replacing the inverter or rearchitecting the system.