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BLUETTI B300K Expansion Battery product image 1

BLUETTI B300K Expansion Battery | 2,764.8Wh

by BLUETTI
Save $600.00
$1,699.00
$1,099.00
Pay as low as $91.58/mo with Shop Pay Installments — 0% APR options available.
✅ In Stock — Ships within 2–4 business days

Notify me when back in stock

🚚 Free Shipping to contiguous US  •  🔁 30-Day Returns  •  💰 Price Match Guarantee  •  🔒 Secure Checkout

🛡 Warranty: Manufacturer warranty included. Coverage varies by product — see product description below for full warranty details.

The B300K is the easiest way to add real runtime to a compatible BLUETTI backup system. Use it when the base power station is right, but the outage, workday, or off-grid stay is longer than one battery can comfortably cover.

Key Features

  • 2,764.8Wh added capacity: Extends runtime for home backup, cabins, RVs, and remote work.
  • LiFePO4 battery chemistry: Designed for long cycle life and safer storage.
  • Works with Apex 300: Adds modular capacity without rebuilding the whole system.
  • 6,000+ life cycles: Built for regular use, not just emergency shelf storage.
  • Standalone USB-A output: Can charge small essentials directly when needed.
  • Expandable backup: Stack multiple batteries for larger energy storage systems.

Specifications

Battery Capacity 2,764.8Wh
Battery Type LiFePO4
Cycle Life 6,000+ cycles
Compatibility Apex 300 and compatible BLUETTI systems
Standalone Output USB-A port for small devices
Use Cases Runtime expansion, home backup, RV power, off-grid power
Warranty 3+1 years with registration

What's Included

  • B300K expansion battery
  • Battery connection cable
  • User documentation

Compatible Add-Ons

  • BLUETTI Apex 300
  • BLUETTI Charger 2
  • Hub D1 power hub
Description

The B300K is the easiest way to add real runtime to a compatible BLUETTI backup system. Use it when the base power station is right, but the outage, workday, or off-grid stay is longer than one battery can comfortably cover.

Key Features

  • 2,764.8Wh added capacity: Extends runtime for home backup, cabins, RVs, and remote work.
  • LiFePO4 battery chemistry: Designed for long cycle life and safer storage.
  • Works with Apex 300: Adds modular capacity without rebuilding the whole system.
  • 6,000+ life cycles: Built for regular use, not just emergency shelf storage.
  • Standalone USB-A output: Can charge small essentials directly when needed.
  • Expandable backup: Stack multiple batteries for larger energy storage systems.

Specifications

Battery Capacity 2,764.8Wh
Battery Type LiFePO4
Cycle Life 6,000+ cycles
Compatibility Apex 300 and compatible BLUETTI systems
Standalone Output USB-A port for small devices
Use Cases Runtime expansion, home backup, RV power, off-grid power
Warranty 3+1 years with registration

What's Included

  • B300K expansion battery
  • Battery connection cable
  • User documentation

Compatible Add-Ons

  • BLUETTI Apex 300
  • BLUETTI Charger 2
  • Hub D1 power hub
Shipping

Shipping is FREE on all orders to customers within USA.

We don't want to mess around with fine print and extra charges, we like things to be simple and easy. 

Want to know about our Returns Policy? Read more here.

Order Confirmation:

As soon as you place your order you will receive an order confirmation e-mail.  This means that we have received your order in our system and pre-authorised your credit card for the purchase.  

As soon as we receive your order we automatically check to confirm that your order is in stock and available for immediate shipment.  If your item is on back-order or unavailable we will void the pre-authorisation and reach out to you via e-mail to see if alternate arrangements can be made.  

If your item(s) are available for immediate shipment (within 5 business days) we will process the charges and get to work preparing your order for shipment.

Order Shipment:

If your order is in stock and we process the charges to your credit card it will ship within three business days from the date of your order.  

We will send you shipping confirmation within 24 hours of your order leaving the warehouse to the e-mail address you provided when checking out.  

If you do not receive shipping confirmation from us within four business days of your order feel free to follow up with us at sales@homesteadheavy.com.

International Orders:

Please be aware that our products are made specifically for the USA market. This means that they require a 110V electrical system to function correctly. 

Our products have generally not been certified for use with other countries electrical safety standards but all of our products are certified to [country of sale] standards.

We will happily ship our fantastic products to international customers. Due to the extremely wide variety of product dimensions we will provide an up to date shipping price quote for you on request.

If you are happy with our shipping quote we will prepare an order and payment though our ultra secure online payment gateway.

Damages:

Please inspect the packaging of your item(s) when they arrive, if you notice any damage you should make note of it when signing for delivery or do not agree to accept the delivery.

If you do accept delivery you are required to immediately take photos using your smart phone or camera of the damaged packaging or products inside the packaging. 

If your item(s) do arrived damaged please send photos to sales@homesteadheavy.com, then visit our Returns page and lodge your return claim online.

Why Buy From Us

We get it. You've got a lot of choice when it comes to online retailers. Here's why we think you should shop with us at Homestead Heavy.

But first, you should definitely hear from our customers here.

  • Free Shipping USA wide. No extra charges. Ever.

  • Price Match Guarantee. Best prices online guaranteed.

  • 30 Day Easy Returns. No happy with your product, we'll take it back no questions asked.

  • Great Service. We pride ourselves on the best service, anywhere.

  • Your Satisfaction Guaranteed. We handpick our products for quality, we know you'll love them. But is there is ever something wrong, we'll fix it.