Big Battery | NEXUS + APEX-6.5K Off-Grid System
Big Battery | NEXUS and APEX-10K Off-Grid Solar Power System Nexus + APEX-6.5K Off-Grid Power System with 15 kWh Battery
This all-in-one energy system pairs a robust APEX-6.5K hybrid inverter with the Nexus 15 kWh LiFePO₄ battery bank to deliver reliable split-phase 120/240 V power for cabins, remote homes, and off-grid properties. Designed to accept both solar and generator inputs, the system provides clean pure sine-wave output and high-capacity performance for essential loads, appliances, and everyday energy demands. Rugged construction, installer-friendly wiring, and scalable configuration options make it a dependable solution for energy independence and resilient power infrastructure.
KEY FEATURES
- integrated APEX-6.5K inverter with 6.5 kW continuous output
- 120/240 V split-phase power for full residential loads
- Nexus 15 kWh LiFePO₄ battery bank with high usable capacity
- accepts both solar and generator charging inputs
- pure sine-wave output for sensitive electronics
- scalable configurations with multiple batteries or inverters
Specifications
| Section | Details |
|---|---|
| Document Title | APEX-6.5K & APEX 10K INVERTER SPECIFICATIONS |
| Brand | BigBattery |
| Model | APEX-6.5K / APEX-10K |
| Rated Output Power | APEX-6.5K: 6,500W / APEX-10K: 10,000W |
| Max. Output Power | APEX-6.5K: 13,000VA / APEX-10K: 20,000VA |
| Rated Output Voltage | 120/240 Vac (single-phase / split-phase) |
| Load Capacity of Motors | APEX-6.5K: 4 HP / APEX-10K: 6 HP |
| Rated Frequency | 50/60Hz |
| Output Wave | Pure sine wave |
| Switching Time | 10ms (typical value) |
| Battery Type | Lithium-ion battery / lead-acid battery / user-defined battery |
| Rated Battery Voltage | 48V |
| Battery Voltage Range | 40–60Vdc |
| Max. Solar Charging Current | APEX-6.5K: 140A / APEX-10K: 200A |
| Max. Grid / Generator Charging Current | APEX-6.5K: 80A / APEX-10K: 120A |
| Max. Hybrid Charge Current | APEX-6.5K: 140A / APEX-10K: 200A |
| Number of MPPTs | 1 + 1 |
| Max. Solar Input Power | APEX-6.5K: 5,000W + 5,000W / APEX-10K: 5,000W + 5,500W |
| Max. Solar Input Current | APEX-6.5K: 18A + 18A / APEX-10K: 22A + 22A |
| Max. Open Circuit Voltage | 550Vdc + 550Vdc |
| MPPT Voltage Range | 125–450Vdc |
| Grid / Generator Input Voltage Range | 65–140Vac |
| Grid / Generator Input Frequency Range | 50/60Hz |
| Bypass Overload Current | APEX-6.5K: 40A / APEX-10K: 63A |
| AC Inputs | APEX-6.5K: 2 inputs (Grid & Generator) / APEX-10K: 1 input (Grid or Generator) |
| Max. Efficiency | 99.9% |
| MPPT Tracking Efficiency | APEX-6.5K: 93% / APEX-10K: 92% |
| Parallel Capacity | Up to 6 units (more than 3 units in parallel can form a three-phase output) |
| Dimensions (W × H × D) | APEX-6.5K: 25.51 × 16.14 × 5.51 in / APEX-10K: 28.46 × 17.64 × 5.91 in |
| Weight | APEX-6.5K: 48 lbs / APEX-10K: 62 lbs |
| Protection Degree | IP20 (indoor only) |
| Operating Temperature | 14–131°F, derate above 113°F |
| External Module (Optional) | Wi-Fi / GPRS |
| Certifications | UL1741 / RoHS / EN61000-6-1 / EN61000-6-3 / FCC Part15 Class B / IEC62109-1 / IEC62109-2 |
| Noise Level | <60dB |
| Cooling Method | Intelligent fan |
| Warranty | 5 years |
| Communication Interfaces | RS485 / CAN / USB / Dry contact |
| Integrated Circuit Breaker | Utility / Load / Battery / PV |
| Overload Protection Behavior | Output restores after 3 minutes. After 5 overloads, output shuts down until restart. (102%–110% load): shutdown after 5 min. (110%–125% load): shutdown after 10 sec. (>125% load): shutdown after 5 sec. |
| Protection Features | PV input current limiting, PV over-voltage, PV night reverse current, AC input over/under-voltage, battery over/under-voltage, battery over-current, AC output short-circuit, heat sink over-temperature, inverter overload protection |
Manual & Downloads
Are Solar Guys Pro Authorized Retailers?
Yes! We are proud to be one of the few online retailers who are authorized retailers for every single product we carry!
Being an authorized retailer means we carry the same warranty as the manufacturer, protecting your purchase!
When Will My Order Ship?
Most orders ship within 1–3 business days. You’ll get a tracking number as soon as it ships via email!
Do We Accept Returns?
Yes absolutely, we have a no-hassle, 30-day return policy on all items! To refer to the full policy, click HERE
Are Products Brand New?
Yes! By default, all products on Solar Guys Pro are 100% brand-new and in perfect condition.
If an item is used or refurbished, it will clearly indicate so in the title of the product as well as the discription.
For example, a used Battery will say:
XYZ Battery | 48V 100AH (REFURBISHED)
If you'd like to confirm, you can always send us a email at info@solarguyspro.com
Orders over $500 include a FREE (Normally $149.99) 80-Page DIY Solar eBook — added automatically at checkout.
Frequently Asked Questions
Get your 30% Tax Solar Credit!
Unlock substantial savings with the government's Solar Tax Credit, which offers a robust 30% deduction on the installation costs of solar systems. This attractive incentive is your ticket to leveraging solar energy's eco-friendly potential while enjoying the financial benefits.
At Solar Guys Pro, our commitment is to you. Please be reminded that our expertise does not extend to tax advice. Nonetheless, our dedicated staff is eager to guide you through the process and ensure you capitalize on this exceptional offer.
Contact us now to learn more!