Bluetti Apex 300 B300K Expansion Battery

BLUETTI B300K Expansion Battery | 2.7kWh LFP Capacity

Extend Your Power, Wherever You Are

The BLUETTI B300K is a dependable 2.7kWh LiFePO₄ expansion battery built to increase the runtime of your BLUETTI power station. Whether you’re keeping a home office running during outages, powering a camper van along Ireland’s coast, or adding extra storage for tools and equipment, the B300K gives you more capacity without changing your existing setup.

Simple, Scalable Energy Storage

Designed around long-life LFP technology, the B300K connects directly to your Apex 300, AC300, AC500, AC200MAX or AC200L using the official expansion cables. Once paired, your system can scale from a single battery to a multi-module bank capable of supporting serious home backup, off-grid living or mobile work.

Fast Charging & Easy Operation

LED indicators keep things simple, the USB-A port provides an easy top-up for small devices, and when paired with an AC300 or AC500, the B300K can recharge from 5% to 80% in around 45 minutes under recommended temperatures. It’s a practical, reliable upgrade for Irish homes, vans, workshops and off-grid setups.

• 2,764.8Wh LFP Battery: Long lifespan, stable and safe daily performance
• Fast Charging: With AC300/AC500, approx. 45 minutes (5% → 80%)
• USB-A Output (12W): Ideal for phones and small devices
• Dual Expansion Ports: Supports multi-battery setups
• Clear LED Indicators: Quick view of battery status
• Pass-Through Capable: When connected to a power station
• Rugged and Durable: Built for Ireland’s mix of home and mobile use

Important Note

The B300K is an expansion battery and is not designed to operate as a standalone unit. It must be connected to a compatible BLUETTI power station.

Compatible Power Stations

The B300K works with the following BLUETTI models:

Power Station	Max B300K (or mix)
Apex 300	Up to 6
AC300	Up to 4
AC500	Up to 6
AC200MAX	Up to 2
AC200L	Up to 2

What’s in the box:  1.Bluetti Apex 300 B300K Expansion Battery, 2. P090A Battery Expansion Cable ( 31.49in / 800mm ), 3. User Manual & Warranty Card.

Product	Bluetti Apex 300 B300K Expansion Battery
Size	52.5 (L) x 32.7 (W) x 20.9 (H) cm
Weight	29.5 kg
Battery Type	LFP (LiFePO4 battery)
Battery Cycles	4000 cycles to 80%+ capacity
Battery Capacity in Wh	2764 Wh
Output USB	USB-A Output (x1):  12W Max, 5V/2.4A
Output Port	Expansion Port (x2): 58.4VDC Max, 90A Max.
Charging Temperature	0°C to 40°C (32°F to 104°F)
Discharging Temperature	-20°C to 40°C (-4°F to 104°F)
Charging Current	60A Max. (Current may decrease outside specified temperatures)
Shelf Life	For long-term storage over 6 months, charge to 40%-60% SoC. Fully cycle every 3 months.

Download the Manual