Discover Energy HELIOS ESS LiFePO4 Battery 16.1 kWh 51.2V 314 Ah Outdoor
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Visit CalculatorThe Discover HELIOS ESS LiFePO4 Battery is a premium, high-capacity outdoor-rated energy storage system designed to deliver reliable power for residential and commercial applications. With 16.1 kWh of usable storage, a rugged IP65-rated outdoor enclosure, and advanced lithium iron phosphate (LiFePO4) chemistry, the HELIOS battery is perfect for whole-home backup, off-grid systems, or scalable hybrid solar configurations. It integrates seamlessly with leading inverter brands and is engineered for safe, efficient, and long-lasting operation in all climates.
High-Capacity Outdoor Energy Storage
16.1 kWh of usable capacity with 314 Ah of lithium power—ideal for whole-home backup or large solar installations.
51.2V LiFePO4 Chemistry
Safe, stable, and maintenance-free lithium iron phosphate cells deliver high cycle life and consistent energy performance.
Rugged IP65 Outdoor Enclosure
Designed for extreme weather conditions with a waterproof and dustproof shell—no need for indoor storage or additional protection.
Smart Integrated BMS
Monitors voltage, temperature, and charge levels in real time while protecting against overvoltage, short-circuit, and thermal events.
Compatible with Leading Inverters
Supports CAN/RS485 protocols for direct communication with hybrid and off-grid inverters including Sol-Ark, Schneider, Growatt, and more.
Scalable & Stackable
Add additional units in parallel to increase total storage capacity for residential, commercial, or microgrid applications.


Everything you need is included with your product.
| Category | Specifications |
| Nominal Voltage | 51.2 V |
| Energy | 16,080 Wh |
| Nominal Capacity | 314 Ah |
| Charge Bulk Voltage - Bulk Vdc | 55.2 – 56.8 V |
| Charge Absorption Voltage - U1 MAX | 55.2 – 56.8 V |
| Charge Float Voltage - U2 | 53.6 V |
| Charge Termination Current (a) | 5 A |
| Low Voltage Disconnect Recommended | 48 V |
| Low Voltage Disconnect (b) | 43.2 V |
| Max Continuous Charge Current (c) | 200 A |
| Max Continuous Discharge Current (c) | 200 A |
| Peak Discharge Current (15 seconds) | 300 A RMS |
| Self Discharge Current (operation) | ≤ 25 mA |
| Self Discharge Current (battery OFF) | ≤ 4 mA |
| Breaker Type | Single-Pole (positive only) 200 A breaker (CVP-RH-P2BD5-D200-LT) |
| Maximum Short Circuit Fault Current (IBF / ½ IBF) | 7.16 kA (100 ms) / 3.58 kA (100 ms) |
| Arc Flash Incident Energy IEm | 0.310 Cal/cm² |
| Arc Flash Incident Energy AFB | 239 mm (9.41 in) |
| Category | Specifications |
| Height (A) | 900 mm (35.43 in) |
| Width (B) | 465 mm (18.31 in) |
| Depth - body only (C) | 247 mm (9.72 in) |
| Depth (including Wall-Mount bracket) | 271 mm (10.7 in) |
| Terminal | Quick Connect Plug and Pull Terminal |
| Weight | 136 kg (299.83 lb) |
| IP Rating | IP65 |
| Case Material | Galvanized Steel Sheet |
| Certifications | UN38.3, UL 1973, UL 9540A, UL 9540 DC ESS 3rd Edition (Pending) |
Can this battery be installed outdoors without extra housing?
Yes. The HELIOS battery includes a fully weather-sealed, IP65-rated outdoor enclosure that protects it from dust, rain, snow, and extreme temperatures.
What inverters is it compatible with?
It supports CAN and RS485 communication protocols, making it compatible with most leading inverter brands such as Sol-Ark, Growatt, and Schneider.
Is it expandable?
Yes. Multiple HELIOS batteries can be connected in parallel to increase overall system capacity for larger storage needs.
Is there a heating function for sub-zero temperatures?
This model is built for outdoor durability but does not include internal heating. It is best used in environments above 0°C unless supplemental protection is provided.
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