11kWh Home Backup System: Rubix 48V LiFePO4 Battery + 12kW Sol-Ark 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 11kWh Home Backup System: Rubix 48V LiFePO4 Battery 12kW Sol-Ark Hybrid Inverter ESS Kit is a pre-matched solar battery backup system that pairs 10.5kWh of LiFePO4 storage with a 9,000W continuous / 12,000W total hybrid inverter — both confirmed compatible on voltage, charging current, and communication protocol so you can skip the component-vetting process entirely. 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 RGS51205 Giga Stack Series Battery — 1× 48V / 205Ah (10.5kWh) LiFePO4 deep cycle battery module.
• Sol-Ark 12K-LV (12K-2P) Hybrid Inverter — 1× 9,000W continuous / 16,000VA peak, 120/240V split-phase.
• Rubix Giga 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, BMS communication protocol, and cutoff thresholds — and getting any one of those wrong means returns, delays, or underperformance. This solar battery storage system bundles the RGS51205 and 12K-LV (12K-2P) as a pre-engineered pair: the inverter's 48V battery port and 185A solar charging current align directly with the Rubix battery's 120A max continuous charge rating, and the Sol-Ark's RS485/CAN communication interface pairs with the Rubix's built-in inverter communication selection — no workarounds needed.

Who this kit fits

• Residential home backup — 11kWh covers lights, refrigeration, and essential appliances through a utility outage, delivered as clean 120/240V split-phase power.
• Off-grid cabin or workshop — pair with a PV array up to 13,000W 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 RGS51205 connects to the Sol-Ark inverter's 48V battery terminals via M8 bolt-on lugs (torqued to 20 ft-lbs). The inverter charges the battery through its MPPT solar input — accepting up to 13,000W of PV at up to 500Vdc open-circuit — and supplements charging from grid or generator at up to 185A. The Stack Series Base positions the battery horizontally, the required orientation per Rubix, and supports up to 3 additional RGS51205 modules in the same physical stack for a single-stack total of 42kWh. Additional parallel stacks extend capacity further, up to 32 units and 336kWh 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 RGS51205 and 12K-LV (12K-2P) are matched at the spec level — not just at the voltage label. The Rubix battery's UL 9540A pending certification addresses fire-safety compliance requirements common in permit-pull residential installations, while the Sol-Ark inverter's UL 1741 SB, IEEE 1547.1-2020, and UL 1699B listings satisfy utility interconnection requirements across most US and Canadian jurisdictions. For buyers building a solar battery backup system for home or small commercial use, that dual-certification combination reduces the compliance research burden that typically comes with sourcing components individually. And because the Rubix Giga 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.