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EG4

BigBattery ETHOS + EG4 FlexBOSS21 | 16kW Hybrid Solar ESS

SKU K0241
$6,675.00
$6,675.00
🔥 — sold in the last —
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Estimated shipping time

You can typically expect your items to arrive within 4–7 business days, depending on your location and product availability.

What is your Return Policy?

At Northgrid Supply, we want every customer to shop with confidence. If something doesn’t go as planned, we’ve made returns and refunds simple and fair. Here’s how it works:

1. Return Window

You can request a return within 30 days of receiving your order. Unfortunately, we’re unable to accept returns after that time frame.

2. Who Pays for Return Shipping?

  • If your item arrives damaged, defective, or incorrect, we’ll cover the return shipping cost.
  • If you’re returning an item because you changed your mind, you’ll be responsible for return shipping fees.

3. Damaged or Defective Items

Received something broken or not working properly? Contact us within 30 days. We’ll provide a prepaid return label and once the item is returned and inspected, we’ll issue either a full refund or a replacement—including any original shipping costs.

4. Changed Your Mind?

If you no longer want the item, you can return it within 30 days—as long as it's unused, in its original packaging, and in resellable condition. You’ll need to handle the return shipping, and once we receive and inspect it, we’ll refund the product cost (excluding shipping).

5. Refund Processing

Once we receive and approve your return, we’ll send a confirmation email and issue a refund to your original payment method within 7 business days. Please allow additional time for banks or credit card companies to process and reflect the refund.

If it’s been over 10 business days since your refund was approved and you still don’t see it, contact us at support@northgridsupply.com and we’ll look into it immediately.

6. Restocking Fees

In some cases, a restocking fee may apply depending on the item and return reason. If applicable, we’ll clearly communicate this during your return request process.

ETHOS EG4 FlexBOSS21 ESS

The ETHOS + EG4 FlexBOSS21 ESS is a fully integrated energy storage system built to support both grid-connected and off-grid setups. It pairs the expandable ETHOS 48V lithium battery platform with the 16kW EG4 FlexBOSS21 hybrid inverter to create a smart, all-in-one solution for managing solar and backup power more efficiently. Backed by U.S.-engineered components and a 12-year battery warranty, this system offers reliable, maintenance-free performance.

Key Features

  • High-Capacity Storage: Features 21kWh of initial energy storage, utilizing stackable LiFePO4 modules.

  • Powerful Hybrid Inverter: Includes a 16kW hybrid inverter designed for demanding residential and commercial applications.

  • Safe LiFePO4 Technology: Uses Lithium Iron Phosphate chemistry for enhanced thermal stability and a 6,000+ cycle life.

  • Modular Expansion: Future-ready design allows battery expansion up to 80+ kWh.

  • Intelligent Management: Features an integrated Battery Management System (BMS) with closed-loop communication.

  • Weather-Resistant: NEMA 4X and IP65 rated enclosure for safe indoor or outdoor installation.

  • Comprehensive Safety: Includes built-in fire protection, overcharge protection, and temperature monitoring.

Performance and Efficiency

  • Whole-Home Power: Delivers split-phase 120/240V output to support heavy household loads.

  • Optimized Solar Harvest: Utilizes multiple MPPT trackers for maximum efficiency across diverse solar arrays.

  • Resilience: The system is engineered for consistent performance across a wide range of energy demands.

Product Details

  • Battery Specifications: Each module offers 10.24kWh capacity with a 51.2V nominal voltage and 200Ah capacity.

  • Inverter Specifications: 16kW output supporting both battery-only and solar-assisted modes.

  • Charging Range: Standard charging voltage range is between 55.6V and 57V.

  • Connectivity: Supports CANBus and RS485 communication protocols for seamless inverter integration.

  • Monitoring: Equipped with an LCD display and remote Wi-Fi monitoring capabilities.

What’s Included

  • ETHOS lithium battery modules.

  • ETHOS Control Box and master BMS unit.

  • EG4 FlexBOSS21 hybrid inverter system.

  • Integrated monitoring system and mounting components.

Applications

  • Residential solar energy storage and whole-home backup.

  • Off-grid installations and peak energy cost management.

  • Commercial energy storage solutions.

Safety and Protection

  • Advanced BMS for real-time regulation of voltage, current, and temperature.

  • Short circuit, overload, and over-discharge protection.

  • UL 9540, UL 9540A, and UL 1973 certified for rigorous safety compliance.

Expandable Design The modular structure allows the system to scale as energy requirements grow. Up to 10 inverter units can be connected in parallel for a combined output of up to 160kW, making it a highly flexible long-term energy solution.

Document Links

Battery Downloads:

Inverter Downloads

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    Total price$14,984.97