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Bluetti B300K2 Expansion Battery – 2,764.8Wh Capacity, LiFePO₄ Technology, Seamless Integration for Extended Power Supply
Expand your Bluetti AC300, AC500, or APEX 300 portable power stations with the Bluetti B300K2 Expansion Battery. Offering a robust 2,764.8Wh of additional energy capacity, this expansion battery is designed to meet the power demands of your daily life or act as a reliable backup during unexpected power outages. With advanced technology and versatile features, the B300K2 ensures a seamless, continuous power supply, whether you’re at home, on the road, or off the grid.
Designed as more than just a battery add-on, the B300K2 is a standalone power hub, capable of charging essential devices directly via its integrated USB-A port. Whether you're camping, experiencing a blackout, or powering equipment in remote areas, this expansion battery is your ultimate energy companion.
Key Features:
Massive Energy Capacity for Every Need: With a 2,764.8Wh capacity, the B300K2 provides substantial power support for both everyday needs and emergency situations, allowing you to run essential devices and keep your home or campsite comfortable.
Unmatched Battery Longevity with LiFePO₄ Technology: Enjoy over 4,000 life cycles with LiFePO₄technology, delivering a long lifespan, enhanced safety, and consistent performance, ensuring your power needs are met for years to come.
Effortless Integration for Seamless Compatibility: The B300K2 seamlessly connects with the AC300, AC500, and APEX 300 power stations, allowing you to expand your energy capacity up to 33,177.6Wh. Customize your setup easily as your power requirements grow.
Versatile Adaptability for Tailored Energy Solutions: The B300K2 is stackable with other B300 series models (B300, B300K, and B300S), offering flexibility for both home and outdoor use. Adapt your energy system to suit your specific needs, whether you're prepping for emergencies or powering off-grid adventures.
Built Tough with Superior Safety and Reliability: Constructed with a durable aluminum casing and featuring AI-BMS technology, the B300K2 is built to withstand tough environments. Its advanced cooling system and wireless components ensure safe and stable operation under any conditions.
Convenient USB-A Port for Essential Device Charging: The B300K2 includes a USB-A port, making it easy to charge phones, tablets, small appliances, and more, so you’re never caught without power for your essential devices.
What’s Included:
1 × Bluetti B300K2 Expansion Battery
1 × Battery Expansion Cable (CA90)
1 × P150D to P090D Cable
1 × User Manual
Specifications
Battery Specifications
Model
B300K
Battery Capacity
2,764.8Wh (51.2V, 54Ah)
Battery Type
LiFePO₄ (Lithium Iron Phosphate)
Cycle Life
4,000+ cycles (to 80% capacity)
Output Specifications
USB-A Output
12W Max., 5V / 2.4A
Total Capacity
2,764.8Wh
General Specifications
Weight
29.5kg (65.04lbs)
Dimensions (L×W×H)
52.5 × 32.7 × 20.9 cm (20.67 × 12.87 × 8.23 in)
Charging Temperature
0°C to 40°C (32°F to 104°F)
Discharging Temperature
-20°C to 40°C (-4°F to 104°F)
Storage Temperature
Up to 1 month: -20°C to 40°C (-4°F to 104°F) Up to 6 months: -20°C to 25°C (-4°F to 77°F)
Working Humidity
5% to 95% RH
Charging Current
60A Max (may reduce outside optimal temperatures)
Discharging Current
70A Max
Expansion Ports
2 × Ports, 58.4VDC Max., 90A Max
Compatibility
AC300, AC500, APEX 300
Shopping Guide
Power Storage & Inverter
Item / Appliance
Typical Power (W)
Usage Time (hrs)
Total Energy Needed (Wh)
Battery Size Needed (Ah) (12V System)
Inverter Size Needed (W)
LED Light Bulb (10W)
10W
5 hrs
50 Wh
4.2 Ah
100W
Phone Charging
5–10W
2 hrs
10–20 Wh
0.8–1.7 Ah
100W
Laptop Charging
50–100W
3 hrs
150–300 Wh
12.5–25 Ah
200W
Ceiling Fan
75W
6 hrs
450 Wh
37.5 Ah
150W
LED TV (32")
60W
4 hrs
240 Wh
20 Ah
150–200W
Refrigerator (Mini)
100W (avg)
8 hrs
800 Wh
66.6 Ah
300–500W
Water Pump (1HP)
750W
1 hr
750 Wh
62.5 Ah
1000W
Microwave Oven
1000W
0.5 hr
500 Wh
41.6 Ah
1200–1500W
Electric Kettle
1500W
0.3 hr
450 Wh
37.5 Ah
2000W
Key Formulas
Purpose
Formula
Example
Energy Consumption (Wh)
Watts × Hours
60W × 4 hrs = 240 Wh
Battery Capacity (Ah)
Watt-hours ÷ System Voltage (V)
240 Wh ÷ 12V = 20 Ah
Inverter Size (W)
Total Watts × 1.25 (for safety margin)
300W × 1.25 = 375W → Use 400W inverter
Total Load Power (W)
Sum of all appliance watts to be used at once
Light (10W) + Fan (75W) = 85W
Runtime (hrs) of Battery
(Battery Ah × Voltage) ÷ Total Load (W)
(100Ah × 12V) ÷ 240W = 5 hrs
How To Choose The Right Products
Need / Application
Recommended Battery
Inverter Size
Notes
Basic lighting + phone charging
50Ah – 100Ah (12V)
100W–200W
For small backup setups
Home office (laptop, fan, TV)
150Ah – 200Ah (12V or 24V)
500W – 1000W
For moderate usage with 4–6 hours of backup
Home backup (fridge, lights)
200Ah+ (24V or 48V recommended)
1000W – 1500W
Ideal for longer backups or heavier loads
Business / shop power backup
300Ah+ (48V system)
2000W – 3000W
Suitable for commercial setups or extended power outages
Why Shop With Us
Why Shop With Ecogrid Supply?
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Built for Energy Independence: Whether you’re powering a cabin, prepping for emergencies, or going off-grid, our products are selected for performance, reliability, and sustainable operation.