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BigBattery APEX-6.5K Off-Grid Inverter

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SKU: INV034
$1,490.00

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The BigBattery APEX-6.5K Off-Grid Inverter Delivers Split-Phase Pure Sine Wave Power For True Energy Independence

When the grid goes down or when you've decided the grid was never part of the plan — you need more than a stopgap solution. You need a system that was built from the ground up to handle the full demands of real life: refrigerators, well pumps, air conditioners, power tools, and everything in between.

The BigBattery APEX-6.5K Off-Grid Inverter is exactly that system. Engineered for residential backup, off-grid cabins, remote homesteads, RV setups, and mobile worksites, the APEX-6.5K is a hybrid inverter that takes energy independence seriously so you don't have to worry about whether the lights stay on.

With a robust 6,500-watt continuous output, split-phase 120/240V pure sine wave electricity, and seamless compatibility with today's best LiFePO₄ battery systems, this inverter is built to be the backbone of a complete, self-sufficient power solution. Whether you're powering a modest off-grid cabin or a full-sized home backup system, the APEX-6.5K is designed to deliver day after day, season after season.

When you purchase the BigBattery APEX-6.5K through Outbound Power, you're not just buying an inverter you're getting the backing of a team that lives and breathes portable and backup power. This unit ships from Texas, comes backed by a 12-year warranty, and includes lifetime USA-based technical support because a power system is a long-term investment, and you deserve long-term support to match.


BigBattery APEX-6.5K Off-Grid Inverter Features

It powers your whole home with true 120/240V electricity

Most inverters only handle half your home's circuits. The APEX-6.5K delivers full split-phase power, so your well pump, air conditioner, dryer, and other 240V appliances all run without any workarounds or limitations.

Pure sine wave output keeps all your devices safe and happy

Cheap inverters produce rough, choppy power that slowly damages motors and electronics. The APEX-6.5K outputs clean, smooth electricity — identical to grid power — so every appliance, from your CPAP to your refrigerator, runs safely and efficiently.

Solar and generator inputs keep you powered day and night

When the sun sets or clouds roll in, your generator picks up the slack automatically. This dual-input flexibility means your system never goes dark, making it perfect for full-time off-grid living or reliable home backup.

The 80A pass-through handles your biggest, hungriest appliances

Heavy loads like central AC units and electric ranges need serious amperage. The built-in 80A pass-through routes generator or grid power directly to those large appliances, protecting your batteries while keeping every critical circuit running strong.

Bottom-entry wiring makes installation clean, fast, and stress-free

Nobody enjoys a messy, complicated install. The APEX-6.5K's bottom-entry wiring design keeps cables organized and routing simple, saving installers and DIY builders significant time and resulting in a professional, tidy setup from day one.

Smart built-in protections guard your entire system automatically

The APEX-6.5K watches over itself with automatic safeguards against overloads, short circuits, and overheating. These built-in protections quietly work in the background, keeping your investment and everything connected to it safe around the clock.

A 12-year warranty and lifetime support back every purchase

Buying a power system is a long-term decision. BigBattery stands firmly behind the APEX-6.5K with a 12-year warranty and lifetime USA-based technical support, so you always have an expert in your corner whenever you need one.


BigBattery APEX-6.5K Off-Grid Inverter Warranty

BigBattery provides a limited warranty policy, ensuring the absence of defects in materials, workmanship, and performance during the warranty period.


What's Included

  • 1 x BigBattery APEX-6.5K Off-Grid Inverter
  • 2 x M6*60mm Expansion Screws
  • 2 x M5*30mm Plastic Expansion Screws
  • 2 x Phillips M6*10mm Screws
  • 2 x Backup M6*10mm Screws
  • 2 x SC35-6 Copper Lugs
  • 4 x Black M3X6mm Screws
  • 1 x Parallel Communication Cable
  • 1 x WIFI Logger (optional)
  • 2 x CT (optional)
  • 1 x User Manual
  • 1 x Warranty Card
  • 1 x Quality Certificate
  • 1 x Outgoing Inspection Report


BigBattery APEX-6.5K Off-Grid Inverter Specification

Document Title APEX-6.5K & APEX 10K INVERTER SPECIFICATIONS
Brand BigBattery
Model APEX-6.5K / APEX-10K
GTIN/UPC 00199874185712 / 00199874999463
Rated Output Power 6,500W / 10,000W
Max Output Power 13,000VA / 20,000VA
Output Voltage 120/240 Vac (Single-Phase / Split-Phase)
Motor Load Capacity 4 HP / 6 HP
Frequency 50/60Hz
Output Waveform Pure Sine Wave
Switching Time 10 ms
Battery Voltage Range 40 – 60Vdc
Max Solar Charging Current 140A / 200A
Max Grid/Generator Charging Current 80A / 120A
Max Hybrid Charging Current 140A / 200A
MPPT Trackers 2 (1 + 1)
Max PV Input Power 5,000W + 5,000W / 5,000W + 5,500W
Max PV Input Current 18A + 18A / 22A + 22A
Max PV Open Circuit Voltage 550Vdc + 550Vdc
MPPT Voltage Range 125 – 450Vdc
Grid/Generator Input Voltage 65 – 140Vac
Input Frequency 50/60Hz
Bypass Overload Current 40A / 63A
AC Inputs 2 (Grid & Generator) / 1 (Grid or Generator)
Max Efficiency 99.9%
MPPT Efficiency 93% / 92%
Parallel Capacity Up to 6 units (3+ units for three-phase)
Dimensions 25.51 × 16.14 × 5.51 in / 28.46 × 17.64 × 5.91 in
Weight 48 lbs / 62 lbs
Protection Rating IP20 (Indoor Only)
Operating Temperature 14°F – 131°F (Derate above 113°F)
Optional Connectivity Wi-Fi / GPRS
Certifications UL1741 / RoHS / EN61000-6-1 / EN61000-6-3 / FCC Part 15 Class B / IEC62109-1 / IEC62109-2
Noise Level <60 dB
Cooling Method Intelligent Fan
Warranty 5 Years
Communication RS485 / CAN / USB / Dry Contact
Integrated Breakers Utility / Load / Battery / PV
Overload Protection Behavior Restores after 3 minutes; shuts down after repeated overloads;
102–110% load shuts down in 5 min; 110–125% in 10 sec; >125% in 5 sec
Protection Features PV current limiting, PV over-voltage, reverse current protection,
AC over/under voltage, battery over/under voltage, over-current,
short circuit, over-temperature, overload protection

BigBattery APEX-6.5K Off-Grid Inverter Manual

BigBattery_APEX-6.5K_Off-Grid_Inverter_Manual

Common Customer Questions

Get answers to the most frequently-asked questions customers ask before placing an order.

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Order Shipping Time
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Most items may be returned within 30 days of delivery. Please refer to our Returns & Exchanges policy to determine what items are eligible. Returns are not accepted beyond 30 days following delivery.

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