This is a paired system: the BigBattery NEXUS 2 battery and the BigBattery APEX-10K hybrid inverter, sold and configured to work together. The NEXUS 2 is a 48V LiFePO4 (Lithium Iron Phosphate) battery rated at 314Ah, or 16kWh of storage per unit. The APEX-10K is a 10,000W continuous pure sine-wave hybrid inverter built for split-phase 120/240V output. One battery will run the inverter, but BigBattery recommends two NEXUS 2 units in parallel to unlock the inverter's full rated output and charging capability. Read the wiring section below before you order a single-battery configuration.
Note: If you would like to review the manufacturer Product Specifications, Warranty, Brochure, etc., for this system, please refer to the "Resources (System Manuals and Warranty)" Tab above on this page.
Why This Pairing Matters
Off-grid and backup systems fail most often not because of a bad battery or a bad inverter, but because the two were never sized to work together. BigBattery designed the NEXUS 2 and APEX-10K as a matched 48V architecture, with the inverter's BMS communication (RS485/CAN) reading state of charge, temperature, and protection status directly from the battery. That coordination is what lets the inverter manage charging and discharging intelligently instead of guessing at battery limits. The NEXUS 2 uses LiFePO4 cells, rated by BigBattery for more than 8,000 cycles, inside an IP54-rated enclosure suitable for indoor or outdoor, floor-standing installation.
Battery Characteristics
Chemistry: LiFePO4 (Lithium Iron Phosphate). Configuration: 48V nominal, 314Ah, 16kWh per NEXUS 2 unit. The battery is a floor-standing, rugged design intended for residential and remote-power installations, not a drop-in lead-acid replacement in a starter or cranking application.
Wiring & Configuration Limits
One NEXUS 2 battery supports up to 7.6kW of continuous battery-powered output. Because the APEX-10K is rated for 10,000W continuous, a single battery will not deliver the inverter's full rated capacity. BigBattery recommends at least two NEXUS 2 batteries in parallel to reach that 10,000W figure. Two batteries in parallel provide 32kWh of combined storage, 628Ah of combined capacity, and up to 15.2kW of continuous battery power, along with enough combined current capacity to support the inverter's maximum 200A solar and hybrid charging rating.
The NEXUS 2 battery bank can be expanded up to 15 units in parallel, for a maximum rated configuration of 241.5kWh. Up to six APEX-10K inverters can be paralleled for increased system output, and three or more inverters in parallel can be configured for three-phase output. The system supports single-phase and split-phase 120/240V applications, and solar, battery, grid-assisted, or generator-assisted operation.
This system is NOT rated for series-only battery stacking to raise voltage beyond the 48V nominal architecture — expansion is parallel, within the stated 48V system design. Do not mix NEXUS 2 units with other battery brands or chemistries in the same bank. A single NEXUS 2 is NOT sufficient to draw the APEX-10K's full 10,000W output or its maximum 200A charging capability — plan for a minimum of two batteries if you need full inverter performance.
Pro-Installer Tip
Undersizing the battery bank relative to inverter demand is the most common configuration mistake on this system. If you run a single NEXUS 2 against the APEX-10K's full 10,000W rating, you're asking one battery to exceed its 150A continuous discharge limit and its 7.6kW continuous power rating, which triggers repeated BMS protection cutouts rather than smooth operation. Over time, that repeated stress at the discharge ceiling accelerates cell wear and can push the BMS into a protective lockout state during peak loads. Pair the system with a shunt-based battery monitor so you can watch real-time amp draw against the 150A continuous / 270A one-second peak limits per battery, and size your bank — two or more NEXUS 2 units in parallel — before you lean on heavy 240V loads. LiFePO4 chemistry supports deep discharge, but plan around the manufacturer's stated capacity and current limits rather than the chemistry's theoretical maximum DoD.
Key Benefits
- 16kWh of LiFePO4 storage per NEXUS 2 battery, rated for more than 8,000 cycles
- 150A continuous battery discharge with a 270A one-second peak rating for surge loads
- 10,000W continuous pure sine-wave output with 20,000W surge capacity from the APEX-10K
- RS485/CAN BMS communication for coordinated charging, discharging, monitoring, and protection
- Dual independent MPPT channels supporting flexible solar-array configuration
- IP54-rated enclosure suitable for indoor or outdoor installation
- Expandable architecture: up to 15 batteries in parallel and up to six inverters in parallel
Technical Table
| Spec | Value |
|---|---|
| Battery Voltage | 48V |
| Battery Capacity | 314Ah |
| Battery Energy | 16kWh |
| Chemistry | LiFePO4 |
| Max Continuous Discharge (per battery) | 150A |
| Peak Discharge (1 second, per battery) | 270A |
| Continuous Battery Power (per battery) | 7.6kW |
| Cycle Life | 8,000+ cycles |
| Enclosure Rating | IP54 |
| Inverter Continuous Output | 10,000W |
| Inverter Surge Capacity | 20,000W |
| Motor Capacity | 6 HP |
| Switching Time | 10ms (typical) |
| Output Configuration | Single-phase and split-phase 120/240V |
| MPPT Channels | 2 independent channels, 5,500W / 22A each |
| MPPT Voltage Range | 125-450VDC |
| Max Open-Circuit PV Voltage | 550VDC |
| Max Solar Charging | 200A |
| Max Grid/Generator Charging | 120A |
| Max Hybrid Charging | 200A |
| AC Bypass Capacity | 63A |
| BMS Communication | RS485 / CAN |
| Two-Battery Combined Storage | 32kWh |
| Two-Battery Combined Capacity | 628Ah |
| Two-Battery Continuous Power | 15.2kW |
| Max Parallel Battery Configuration | 15 batteries / up to 241.5kWh |
| Max Parallel Inverters | 6 |
| Battery Warranty | 12 Years |
| Inverter Warranty | 5 Years |
Note: See "Resources (System Manuals and Warranty)" Tab above for full specifications.
Options & SKUs
| Variant | SKU | Price |
|---|---|---|
| variable parent (7 variations) | K0338-V | $4605.00 |
[NEEDS VERIFICATION]: The manufacturer data references 7 configurable variations under this parent SKU, but individual variant titles, SKUs, and prices for each configuration were not provided. Confirm exact configuration (battery count, inverter count) and pricing before ordering.
Compatibility & Fitment
Compatible with: BigBattery APEX-10K hybrid inverter paired with BigBattery NEXUS 2 48V LiFePO4 batteries, matched through RS485 or CAN BMS communication. Supports solar charging (up to 200A combined, 11,000W max array input across two MPPT channels), grid or generator charging (up to 120A), and hybrid charging combining sources (up to 200A). Expandable to 15 batteries in parallel and 6 inverters in parallel, with 3+ inverters supporting three-phase output.
NOT compatible with non-BigBattery batteries or inverters in the same communication loop. NOT a starter or cranking battery. Standard lead-acid chargers are NOT recommended for the NEXUS 2 — charging must go through the paired APEX-10K or another BMS-compatible LiFePO4 charging source. A single NEXUS 2 is NOT sufficient to reach the APEX-10K's full 10,000W output or 200A charging rating. Series-stacking of NEXUS 2 batteries beyond the 48V nominal architecture is NOT supported by the data provided.
FAQ
Q: Can I run the APEX-10K with just one NEXUS 2 battery?
A: Yes, one NEXUS 2 will power the inverter, but it supports only up to 7.6kW of continuous battery power. To reach the APEX-10K's full 10,000W output, BigBattery recommends at least two NEXUS 2 batteries in parallel.
Q: How many batteries can I add to this system?
A: The NEXUS 2 battery bank can be expanded up to 15 units in parallel, for a maximum rated configuration of up to 241.5kWh.
Q: What is the peak discharge rating of the NEXUS 2?
A: 270A for one second, intended to support short equipment-startup surge demands. Continuous discharge is rated at 150A.
Q: Does this system support split-phase 240V loads?
A: Yes, the APEX-10K is configurable for single-phase and split-phase 120/240V applications.
Q: What is the warranty on this system?
A: The NEXUS 2 battery carries a 12-year warranty and the APEX-10K inverter carries a 5-year warranty, backed by lifetime USA-based tech support.
Warranty & Support
Battery warranty: 12 years. Inverter warranty: 5 years. Support: Lifetime USA-based tech support. Ships from Texas, USA. If you're unsure how many batteries or inverters your load profile requires, ask us before you order — we always reply back.
