BigBattery NEXUS + APEX-10K Off-Grid ESS Bundle

Meet the BigBattery NEXUS + APEX-10K Off-Grid ESS Bundle—an expandable 48V energy storage system built around a split-phase 120/240V hybrid inverter and modular LiFePO4 battery capacity. Choose 1, 2, or 3 NEXUS batteries to scale from 15kWh to 45kWh of storage.

Key Features & Benefits

• Split-phase 120/240Vac output (50/60Hz) — Powers true split-phase loads and essential circuits with clean AC power.

• 10,000W rated inverter output (pure sine wave) — Runs demanding appliances and tools with stable, utility-like waveform.

• 20,000VA max output power — Adds headroom for higher-demand situations (within system limits).

• Dual MPPT solar charging (1 + 1 MPPT) — Lets you manage two PV input channels for flexible array design.

• Solar + grid/generator charging support — Multiple ways to recharge so you can keep power available beyond sunlight hours.

• Parallel expandable (up to 6 inverter units) — Grow your system over time; 3+ units can form three-phase output (per spec).

• NEXUS LiFePO4 chemistry — Built for safety, long service life, and efficient energy storage.

• NEXUS integrated BMS + safety features — Includes integrated BMS with quadruple safety redundancies, plus self-heating and integrated aerosol fire suppression (battery features).

• Modular battery growth (up to 15 NEXUS in parallel) — Scale storage up to 225kWh per inverter (15 batteries in parallel).

Specs in a Glance: 

APEX-10K Off-Grid Hybrid Inverter (48V)

• Rated output power: 10,000W

• Max output power: 20,000VA

• Output voltage: 120/240 Vac (single-phase / split-phase)

• Frequency: 50/60Hz

• Waveform: Pure sine wave

• Switching time: 10ms (typical)

• Rated battery voltage: 48V (40–60Vdc range)

• Max solar charging current: 200A

• Max grid/generator charging current: 120A

• MPPTs: 1 + 1

• Max PV input power: 5,000W + 5,500W

• Max PV input current: 22A + 22A

• Max PV open-circuit voltage: 550Vdc + 550Vdc

• MPPT voltage range: 125–450Vdc

• AC input voltage range: 65–140Vac

• AC inputs: 1 input (Grid or Generator)

• Protection degree: IP20 (indoor only)

• Operating temperature: 14–131°F (derate above 113°F)

• Dimensions: 28.46 × 17.64 × 5.91 in

• Weight: 62 lbs

• Communications: RS485 / CAN / USB / Dry contact

• Certifications: UL1741 / RoHS / EN61000-6-1 / EC61000-6-3 / FCC Part15 Class B / IEC62109-1 / IEC62109-2

• Warranty: 5 years

NEXUS 48V 15kWh LiFePO4 Battery (each)

• Usable energy: 15kWh

• Nominal voltage: 51.2V (48V system)

• Capacity: 300Ah (16S1P)

• Chemistry: LiFePO4

• Max continuous discharge current: 140A

• Max continuous power: 7.6kW

• Peak discharge current: 270A (1s)

• Max charge current: 140A

• Charge temp range: 32°F to 113°F

• Discharge temp range: -4°F to 113°F

• Protection rating: IP54

• Installation: Indoor, floor-standing

• Dimensions: 19.7 × 27.5 × 15.7 in (500×700×400 mm)

• Weight: ~315 lbs

• Max connections: 15 in parallel (up to 225kWh)

• Communications: RS485 / RJ45 / CAN

• Warranty: 12 years

What’s Included:

• 1× BigBattery APEX 10K off-grid hybrid inverter

• Choose: 1× / 2× / 3× BigBattery NEXUS 15kWh LiFePO4 battery

Ideal For

• Off-grid cabins, homesteads, and remote residences needing true 120/240V split-phase

• Scalable energy storage builds where you want 15kWh steps up to 45kWh

• Systems that need solar charging + optional grid/generator charging paths

• Indoor mechanical/utility spaces (battery is indoor floor-standing; inverter IP20 indoor-rated)

User Manual / Documents:

• BigBattery 48V 15kWH NEXUS LiFePO4 Battery Spec Sheet
• BigBattery 48V 15kWH NEXUS LiFePO4 Battery User Manual
• BigBattery APEX 10K Off-Grid Hybrid Inverter Spec Sheet
• BigBattery APEX 10K Off-Grid Hybrid Inverter User Manual