BLUETTI B300K LiFePO4 Expansion Battery (For Apex 300)
MPN No: B300K
Expected ship date Sep 24 - 27
In Stock
1,200.00
-17%
$989.00
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B300K
MPN No: B300K
Expected ship date Sep 24 - 27
In Stock
1,200.00
-17%
$989.00
Compatible with BLUETTI Apex 300, AC200L, AC200MAX, AC300 and AC500 power stations.
Manufacturer Part Number: B300K
Add 2,764.8Wh of battery storage to a compatible BLUETTI power station with the B300K. Built with automotive-grade lithium iron phosphate cells and an integrated battery management system, it is designed for frequent cycling, dependable backup power and flexible system expansion.
One B300K adds approximately 2.76kWh of nominal capacity. Use it to extend runtime during grid outages, support longer off-grid stays or expand an existing BLUETTI system as your energy needs grow.
Know before you buy: The B300K is an expansion battery, not a complete power station. It requires a compatible BLUETTI power station for household AC output. By itself, it can only supply power through its built-in 12W USB-A port. Cable requirements vary by power-station model, so review the compatibility table below before ordering.
| Power Station | Supported B300K Quantity | Maximum Total Capacity | Connection Notes |
|---|---|---|---|
| Apex 300 | Up to 6 per Apex 300 | 19,353.6Wh with one Apex 300 and six B300K batteries | CA90 connection; multi-Apex systems require the appropriate Hub A1 configuration |
| AC300 | Up to 4 B300/B300K batteries | 11,059.2Wh with four B300K batteries | P090A connection cable; AC300 has no internal battery |
| AC500 | Up to 6 B300K batteries | 16,588.8Wh with six B300K batteries | P150D-to-P090D cable required and sold separately; AC500 has no internal battery |
| AC200L | Up to 2 B300K batteries | 7,577.6Wh including the AC200L's internal battery | P090A connection cable |
| AC200MAX | Up to 2 B300K batteries | 7,577.6Wh including the AC200MAX's internal battery | P090D connection cable |
Important: Cable names, included accessories and supported mixed-battery configurations can vary by package and power-station generation. This listing includes only the accessories specifically shown in the “What’s Included” section. Contact us before ordering if you plan to mix B300K, B300, B300S, B230 or B210 batteries.
The examples below show the approximate additional runtime one B300K may provide when connected to a compatible power station.
| Example Load | Assumed Power Draw | Estimated Added Runtime |
|---|---|---|
| Wi-Fi router | 20W | Approximately 117 hours |
| CPAP machine | 50W | Approximately 47 hours |
| Laptop | 60W | Approximately 39 hours |
| Full-size refrigerator | 150W average | Approximately 15.5 hours |
| Large television | 200W | Approximately 11.5 hours |
| Continuous medium load | 500W | Approximately 4.7 hours |
Estimates use 85% of nominal battery capacity to account for typical conversion losses. Actual runtime varies with the connected power station, inverter efficiency, operating temperature, battery condition, appliance cycling and standby consumption. The B300K does not determine the system's AC output wattage; output is limited by the connected power station.
Check your connection: The standard package above includes a CA90 cable. AC200L, AC200MAX, AC300 and AC500 installations can require a different cable. Those model-specific cables are not included unless they are expressly shown as part of the selected offer.
| Specification | Details |
|---|---|
| Manufacturer | BLUETTI |
| Model / Part Number | B300K |
| Product Type | Expansion battery |
| Battery Chemistry | Lithium Iron Phosphate (LiFePO₄) |
| Battery Capacity | 2,764.8Wh |
| Nominal Voltage / Amp-Hours | 51.2V / 54Ah |
| Cycle Life | 6,000+ cycles to 80% of original capacity |
| Battery Management | Integrated BLUETTI battery management system |
| Compatible Power Stations | BLUETTI Apex 300, AC200L, AC200MAX, AC300 and AC500 |
| USB Output | USB-A, 5V / 2.4A, 12W maximum |
| Maximum Charging Current | 60A |
| Maximum Discharging Current | 70A |
| Expansion Ports | 2 × 58.4V DC maximum, 90A maximum |
| Charging Temperature | 32°F to 104°F (0°C to 40°C) |
| Discharging Temperature | -4°F to 104°F (-20°C to 40°C) |
| Working Humidity | 5% to 95% RH |
| Dimensions (L × W × H) | 20.67 × 12.87 × 8.23 in (52.5 × 32.7 × 20.9 cm) |
| Weight | 65.04 lb (29.5 kg) |
| Standard Included Cable | CA90 battery connection cable |
| Warranty | 3 years standard, plus 1 additional year with eligible product registration |
No. The B300K stores energy but does not provide household AC output by itself. Connect it to a compatible BLUETTI power station for AC power and full system operation.
The B300K is compatible with the BLUETTI Apex 300, AC200L, AC200MAX, AC300 and AC500. Each platform has its own battery quantity and connection-cable requirements.
The standard B300K package includes a CA90 cable for Apex 300 and B300K-to-B300K connections. AC200L and AC300 use a P090A connection, AC200MAX uses P090D, and AC500 requires a P150D-to-P090D cable. Confirm what is included with the selected package before ordering.
Each B300K adds 2,764.8Wh, or approximately 2.76kWh, of nominal battery capacity to a compatible system.
A single Apex 300 supports up to six B300K batteries, AC300 supports up to four, AC500 supports up to six, and the AC200L and AC200MAX each support up to two. Larger multi-Apex systems can use up to three Apex 300 units and 18 expansion batteries for approximately 58kWh of total capacity.
Some BLUETTI systems support mixed battery models, but the permitted combinations differ by power station. Do not assume every B300, B300S, B230 or B210 combination is supported. Contact us with your exact power station and existing battery models so we can verify the configuration.
Yes, but only through its built-in USB-A port, which is rated at up to 12W. A compatible BLUETTI power station is required for AC outlets and higher-power loads.
No. BLUETTI does not list power-bank mode as supported on the B300K. Its independent output is limited to the 12W USB-A port.
The B300K does not have a conventional solar-input port. Solar charging is normally handled through the connected BLUETTI power station or a supported BLUETTI ecosystem accessory configured for the battery.
BLUETTI states that the B300K can reach 80% in as little as 45 minutes when paired with an AC300 or AC500 under a supported high-power charging configuration. Actual charging time depends on available input power, settings, temperature and battery state.
Runtime depends on the appliance load and the efficiency of the connected power station. As a planning estimate, usable watt-hours can be calculated as 2,764.8Wh × 0.85, then divided by the appliance wattage. For example, a continuous 200W load may receive approximately 11.5 additional hours.
The battery management system maintains operating reserves to protect the cells, and some energy is also lost during DC-to-AC conversion. This is normal for lithium battery systems and is why actual delivered energy is lower than the nominal 2,764.8Wh rating.
Do not treat the B300K as a permanently weather-exposed battery. Keep it dry and operate it within the manufacturer's environmental limits. Use only in a location and configuration permitted by the BLUETTI manual.
The standard manufacturer package includes one B300K expansion battery, one CA90 battery connection cable and one user manual. Model-specific adapters for other power stations are separate unless the offer expressly includes them.
The B300K includes a three-year manufacturer warranty, with one additional year available through eligible BLUETTI product registration. Registration requirements and final coverage terms are controlled by the manufacturer.
BLUETTI develops portable power stations, expansion batteries and home-backup products for grid outages, mobile power and off-grid applications. Its modular product ecosystem allows customers to start with the capacity they need today and expand supported systems later.
US Solar Supplier is an American-founded company based in Kentucky. We offer dependable inventory, competitive pricing and products from established manufacturers with warranties you can trust.
More importantly, our team can help confirm compatibility, connection cables and the right battery configuration before you order. That matters with modular BLUETTI systems, where the correct accessories depend on the power station you own.
Call 1-800-230-7004 for help with product details, compatibility questions or purchasing support.