Your BLUETTI power station is the heart of your energy system, but its potential is truly unlocked with the right expansion battery. Whether you're preparing for extended home backup during power outages or looking to lengthen your off-grid adventures, expansion batteries provide the extra energy reserve you need to stay powered.
BLUETTI offers two exceptional options for scaling up your energy storage: the B500K and the B300K Expansion Batteries. Both are powerful, reliable choices built with advanced LiFePO₄ technology—the safest and most durable battery chemistry available for home energy storage—but they cater to different priorities. This article will help our Canadian customers understand the key differences between the B500K and B300K, making it easy to decide which battery is the perfect fit for your specific power needs.
At a Glance: B500K vs. B300K Side-by-Side
|
Feature |
B500K Expansion Battery |
B300K Expansion Battery |
|
Capacity |
5,120Wh |
2,764.8Wh |
|
Battery Type |
LiFePO₄ |
LiFePO₄ |
|
Life Cycles |
4,000+ to 80% capacity |
6,000+ to 80% capacity |
|
Weight |
45 kg / 99.21 lbs |
29.5 kg / 65.04 lbs |
|
Standalone Ports |
None |
1 x 12W Max (5V / 2.4A) USB-A Port |
|
Warranty |
3+1 Years* |
3+1 Years* |
|
Primary Compatibility |
Apex 300, AC200L, AC200MAX, AC300, AC500 |
Apex 300, AC200L, AC200MAX, AC300, AC500 |
*Both batteries come with a 3-year warranty, extendable to 4 years upon product registration.
The B500K—For Maximum Capacity and Home Backup
Unbeatable value, unmatched capacity—that's the promise of the BLUETTI B500K. With a massive 5,120Wh capacity, it's the premier choice for users with significant power demands. With nearly double the capacity of a B300K in a single unit, it's the most efficient way to maximize your storage per square foot. This makes it ideal for long-lasting whole-home backup, running a small business, or simply minimizing the number of battery units required for a large-scale power system.
While the B500K doesn't have built-in output ports for standalone use, it is designed to integrate perfectly into the BLUETTI ecosystem. When you need to power DC devices, it pairs seamlessly with components like the Hub D1 to deliver reliable energy.
The ideal B500K user is someone whose primary goal is achieving the largest possible energy reserve in a robust, stationary power system for home or business use.
The B300K—For Flexibility and Longevity
The BLUETTI B300K offers a superb balance of substantial capacity, portability, and exceptional durability. Its most impressive feature is an incredible lifespan of 6,000+ life cycles, making it the definitive choice for those who prioritize long-term performance and reliability. This exceptional durability translates to over a decade of reliable daily use, making the B300K the ultimate choice for long-term value and performance.
Weighing 65.04 lbs (29.5 kg), the B300K is significantly lighter than the B500K, which makes it a more manageable and flexible option. It's easier to move and reconfigure, suiting users who may need to adjust their setup from time to time. Adding to its versatility, the B300K includes a practical, regulated 12W USB-A port. This allows you to charge essential devices like phones and tablets directly from the battery, even when it's not connected to a power station.
The ideal B300K user is someone who values a blend of significant power, enhanced portability, and the longest possible battery lifespan.
Seamless Integration: Compatibility & Scalability
Both the B500K and B300K are engineered for seamless integration with BLUETTI's most powerful stations, ensuring you can build and expand your system with confidence and without compatibility issues.
Both batteries are compatible with the following BLUETTI power stations:
-
Apex 300
-
AC500
-
AC300
-
AC200L
-
AC200MAX
The BLUETTI ecosystem is built for scalability. For example, you can connect up to six B300K batteries or six B500K batteries to a single Apex 300 unit. This modular approach allows you to create a massive power reserve tailored to your needs—up to a staggering 33.4kWh with six B500K batteries or over 19.3kWh with six B300K batteries connected to an Apex 300.
Apex 300 + Expansion Battery System Estimated Runtime Table
The Apex 300 offers 2,764.8Wh of base capacity and 3,840W of output power. When paired with expansion batteries, your total system capacity and runtime increases dramatically:
|
Appliance (Approximate Load) |
Apex 300 + B300K (5,529.6Wh) Runtime |
Apex 300 + B500K (7,884.8Wh) Runtime |
|
Wi-Fi Router (20W) |
118.01 hours (4.92 days) |
168.11 hours (7.00 days) |
|
Laptop (60W) |
59.00 hours (2.46 days) |
84.06 hours (3.50 days) |
|
TV (150W) |
27.77 hours |
39.56 hours |
|
Space Heater (350W) |
12.76 hours |
18.17 hours |
|
Refrigerator (700W) |
6.56 hours |
9.34 hours |
|
Microwave (1,000W) |
4.63 hours |
6.59 hours |
|
Central AC (3,000W) |
1.56 hours |
2.23 hours |
Making Your Choice: Which Battery is Right for You?
Use this simple guide to determine the best fit for your needs.
Choose the B500K if...
-
Your priority is maximizing raw energy storage for complete peace of mind during extended outages.
-
You're building a large, stationary system and want the highest energy density to minimize the number of units.
-
Your goal is maximizing your energy storage (kWh) to get the most power from the smallest footprint.
Choose the B300K if...
-
You are investing for the long-haul and demand the absolute best in battery longevity and durability.
-
You value system flexibility and need a more manageable battery that's easier to move and reconfigure.
-
You appreciate the practical convenience of a standalone USB port for charging essential devices directly, anytime and anywhere.
The Final Word: Your Power, Your Choice
Both the B500K and the B300K are excellent LiFePO₄ expansion batteries that deliver on BLUETTI's promise of safe, reliable power. The right choice ultimately comes down to your personal priorities. If your goal is maximum capacity for a stationary home or business backup system, the B500K is the clear winner. If you seek a more flexible and portable solution with an industry-leading lifespan, the B300K is the perfect match.
Build your perfect power system today. Explore the B500K and B300K product pages to finalize your choice.
