BLUETTI B300K expansion battery front view
BLUETTI B300K for Apex 300 expansion battery front view
BLUETTI B300K for Apex 300 expansion battery side view
B300K

BLUETTI B300K Expansion Battery

Add 2,764.8Wh of modular BLUETTI capacity to compatible home and off-grid systems.

  • 2,764.8Wh capacity
  • Automotive-grade LiFePO4 battery chemistry
  • 4,000+ cycles to 80% original capacity
  • Designed for BLUETTI AC200L, AC200MAX, AC300 and AC500
  • Standalone 12W USB-A output

Use with a compatible main unit. Compatibility should be checked before ordering.

£1,099.00

Out of stock

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Quick fit check

Is this expansion battery right for you?

Good fit if:

  • You already own a compatible Bluetti main unit.
  • You want to extend runtime for longer outages or trips.
  • You have checked the connector and model compatibility.

Not ideal if:

  • You need a standalone power station.
  • You have not confirmed compatibility with your existing setup.
  • You want built-in AC sockets directly on the battery.
At a glance

B300K at a Glance

Capacity2764.8Wh
Warranty3+1
Battery TypeLiFePO4
A closer look

A Closer Look at the B300K

B300K is built for customers extending a BLUETTI system rather than buying a standalone inverter. It can act as a limited standalone USB-A power source, but its main role is increasing runtime on compatible host power stations.

BLUETTI B300K for Apex 300 expansion battery side view
VoltReady confidence

Why Buy From VoltReady™

UK-Based Business

VoltReady is a UK-based portable-power specialist serving customers across the United Kingdom.

Manufacturer Warranty

Products include manufacturer-backed warranty cover, with the exact terms shown clearly on each product page.

Flexible Ways to Pay

Pay securely by card, Apple Pay, Google Pay, Klarna or Clearpay. Available options depend on your order and eligibility.

UK Customer Support

Get straightforward help before and after your purchase through live chat or email.

Product details

Everything important, clearly organised

Key Features
2,764.8Wh capacity
Automotive-grade LiFePO4 battery chemistry
4,000+ cycles to 80% original capacity
Designed for BLUETTI AC200L, AC200MAX, AC300 and AC500
Standalone 12W USB-A output
App monitoring through compatible host systems
Technical Specifications
ModelB300K
Capacity2,764.8Wh
Battery TypeLiFePO4
Life Cycles4,000+ to 80% original capacity
USB-A Output12W max
Weightapprox. 29.5kg
Dimensions525 x 327 x 209mm
Charging Temperature0C to 40C
Discharging Temperature-20C to 40C
Expansion Ports2
What’s in the Box
BLUETTI B300K expansion battery
Expansion cable or accessory pack where supplied by channel
User documentation
Warranty documentation
FAQs

Can the B300K be used alone?

Only in a limited way. It has a 12W USB-A output, but it is primarily an expansion battery for compatible BLUETTI power stations.

Can it be charged from solar by itself?

No. The manufacturer states B300K should be charged by connecting it to a compatible host power station.

Can it mix with other BLUETTI batteries?

Some host systems support mixed B300K configurations, but the exact combination and cables must be verified before purchase.

Shipping, Returns & Warranty
Free UK delivery available on qualifying orders.
30-day returns policy for eligible unused items.
Manufacturer warranty applies where verified and is subject to the manufacturer terms.
Delivery times, courier limits, mainland/remote-area handling and heavy-item carriage must be reconfirmed before relaunch activation.
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