SUN-BK250-2.56KWH All-in-one

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Deye SUN-BK250 2.56 kWh – all-in-one micro-hybrid energy storage system (balcony power plant with storage)

The Deye SUN-BK250 is a “3-in-1” micro-hybrid energy storage system that combines a micro-inverter and a 2.56 kWh LFP battery in a single compact unit. The SUN-BK250 flexibly switches between hybrid (grid-tied), off-grid, and AC-coupled modes, making it suitable for reducing energy costs, outdoor power supply, and upgrading an existing balcony solar system with smart storage. It features up to 2.5 kW AC output and 4 independent MPPT channels, and thanks to its IP65 rating, it can be installed outdoors.

Why choose the Deye SUN-BK250 system?

The Deye SUN-BK250 energy storage is based on safe LiFePO4 (lithium iron phosphate) cell chemistry, with a lifespan of over 6000 cycles. The system operates with up to 96.5% DC-AC efficiency, provides UPS-level uninterruptible supply with ≤4 ms grid/island switching, and thanks to its plug-and-play design, can be connected to any standard outlet. Through the Deye Cloud app, up to 6 programmable charge/discharge periods can be set to avoid peak tariffs, while the Deye Copilot function automatically selects the most favorable times based on dynamic electricity prices.

Key advantages of the Deye SUN-BK250

• 3-in-1 flexibility – hybrid, off-grid, and AC-coupled modes in a single unit
• Strong performance – up to 2.5 kW rated AC power, peak power twice the rated (10 s)
• 4 independent MPPTs – flexible PV input, 18L version up to 4400 W, 32L version up to 5760 W PV power
• UPS-level backup – ≤4 ms grid/island switching
• IP65 protection – dust and waterproof, for outdoor installation
• Smart energy management – 6 programmable periods, intelligent load control, wireless zero-export, Deye Cloud App
• Expandable storage – with AE-F2.56 battery packs up to 5 modules vertically (12.8 kWh), total of 40 packs (102.4 kWh)
• Wide compatibility – for 80–250 W micro-inverters, AC-coupled connection to most European balcony micro-inverters
• Long lifespan and solid backing – >6000 cycles and 10-year warranty

Applications

The Deye SUN-BK250 micro-hybrid energy storage is ideal in three scenarios: as a compact balcony solar power plant to increase self-consumption and reduce bills, as a portable power source for camping and outdoor activities, and as a reliable home backup power source during outages. The 2.56 kWh storage is sufficient to cover evening consumption, run backup devices, and still have capacity left for the next morning. Compatible with devices ≤2500 W – such as smaller kitchen and household appliances, lighting, routers, and entertainment electronics.

Deye SUN-BK250-2.56KWH technical specifications

Frequently asked questions about the Deye SUN-BK250 system

What does the SUN-BK250 designation and 18L/32L mean?
The “250” refers to the maximum 2500 W AC power (the series consists of 80/160/200/250 W models, i.e., 800–2500 W). The “18L” and “32L” indicate the PV input capacity: the 18L version accepts up to 4400 W, the 32L version up to 5760 W PV power – both with the same 2.56 kWh LFP storage and 4 MPPT channels.

Can the Deye SUN-BK250 storage capacity be expanded?
Yes. Compatible with AE-F2.56 battery packs: up to 5 modules (12.8 kWh) can be stacked vertically, and a total of up to 40 packs (102.4 kWh) can be connected, with the same control unit, app, and 10-year warranty.

Can the Deye SUN-BK250 be installed outdoors?
Yes, thanks to its IP65 rating it is dust and waterproof, so it can be used outdoors, on balconies; with optional heating it operates down to −20 °C.

Can it be used with an existing balcony solar system?
Yes. In AC-coupled mode it can be connected to most European balcony micro-inverters without rewiring – so an existing balcony power plant can be upgraded with smart storage.