Expansion battery entity · 2.76 kWh LiFePO4 expansion · Current
BLUETTI B300K Expansion Battery
2,764.8 Wh LiFePO4 expansion battery for BLUETTI's AC-series stations (AC200L, AC200MAX, AC300, AC500), 29.5 kg. Adds capacity to the host and carries a single 12 W USB-A as its only outlet, with no direct AC, solar or car charging of its own. How many chain depends on the host, from 2 up to 6.
Machine summary · expansion_battery · bluetti-b300k
- brand
- BLUETTI
- model_name
- B300K
- release_status
- current
- chemistry
- lifepo4
- capacity_wh
- 2764.8
- compatible_host_models
- AC200L, AC200MAX, AC300, AC500
- has_own_outlets
- true
- weight_kg
- 29.5
- confidence_level
- high
- source_last_checked
- 2026-08-15
- json_export
- /expansion-batteries/bluetti-b300k.json
Overview
The BLUETTI B300K is a 2,764.8 Wh LiFePO4 expansion battery (54 Ah at 51.2 V nominal) in a 29.5 kg case, built to enlarge BLUETTI's AC-series power stations. BLUETTI states it integrates with the AC200L, AC200MAX, AC300 and AC500. It has almost no output of its own: a single USB-A port rated 12 W (5 V / 2.4 A), and BLUETTI's own FAQ answers 'No' to solar and car charging on the unit, so it can only be recharged through its host. The number of expansion units per host varies by model: 2 on the AC200L, 2 on the AC200MAX, 4 on the AC300 and 6 on the AC500. Warranty is 3 years base, extended to 4. A serious variant hazard applies here: a separate 'B300K for Apex300' SKU (prefix B300K2-) shares the name, and the bundle product page bleeds that variant's Apex 300 compatibility, a 6,000-cycle figure and a bundled charger accessory's specs into the base record. This record is anchored only on the canonical B300K page and its manual, which describe the AC-series unit rated for 4,000-plus cycles. No cycle count is published here as a DoD-qualified rating because the manufacturer states capacity retention (80%) rather than a depth-of-discharge basis.
Variant note: Canonical B300K expansion battery for the AC-series (AC200L/AC200MAX/AC300/AC500). NOT the 'B300K for Apex300' SKU (prefix B300K2-), which is a different, non-interchangeable product despite the shared name.
Data note: Values anchored ONLY on the canonical BLUETTI B300K expansion-battery page and its manual PDF (2026-08-15). SERIOUS VARIANT HAZARD preserved: a separate 'B300K for Apex300' SKU (prefix B300K2-) shares the B300K name. The /products/b300k bundle page bleeds that variant's Apex 300 compatibility and a 6,000-cycle figure into the base record, and bleeds a bundled Charger 2 accessory's solar input, IP20 rating, 1.59 kg weight and small dimensions into the spec table. None of those belong to this unit: the AC-series B300K is 29.5 kg, 4,000-plus cycles, AC200L/AC200MAX/AC300/AC500 only, no direct charging. maxChainable is null because it varies by host: AC200L 2, AC200MAX 2, AC300 4, AC500 6 (recorded here rather than as a single number that would misrepresent the others). cycleLifeCycles is null by policy: the 4,000-plus figure is quoted to 80% capacity retention, not a depth-of-discharge basis. hasOwnOutlets is true, justified by the single 12 W USB-A port. Storage temperature is not stored as a single range because BLUETTI publishes duration-dependent windows (-20 to 40 C for up to 1 month, -20 to 25 C for up to 6 months); collapsing them to one range would hide the duration dependence. Hero image is a clean BLUETTI 3D render (provenance noted).
Specifications
Host compatibility leads this table because it is what makes an expansion battery meaningful, and it is recorded verbatim from the manufacturer and never inferred. The capacity shown is this unit's own rated energy, not a combined host-plus-expansion system total. Any cycle-life figure carries the depth of discharge it is quoted at, and figures the manufacturer does not publish are left blank rather than estimated. Exact claims and links are in the provenance table.
| Attribute | Value |
|---|---|
| Official compatibility statement | Effortlessly integrates with BLUETTI AC200L, AC200MAX, AC300, and AC500 power stations |
| Host models named by the manufacturer | AC200L, AC200MAX, AC300, AC500 |
| Expansion units the host supports | Not stated |
| Attribute | Value |
|---|---|
| Rated energy | 2,764.8 Wh |
| Rated capacity | 54 Ah |
| Nominal voltage | 51.2 V |
| Chemistry | LiFePO4 (lithium iron phosphate) |
| Attribute | Value |
|---|---|
| Outlets on the expansion unit itself | One USB-A, 12 W max (5 V / 2.4 A). This is the unit's only output port; it has no AC outlets. |
| Direct charging inputs | None direct: the B300K charges only through its host station. BLUETTI's FAQ explicitly answers 'No' to solar and car charging on the unit itself. |
| Attribute | Value |
|---|---|
| Rated cycle life | No cycle-life figure published |
| Cycle-life test conditions | BLUETTI rates the canonical AC-series B300K at 4,000-plus cycles to 80% of original capacity. That is a capacity-retention figure, not a depth-of-discharge basis, so no DoD-qualified cycle count is stored. A 6,000-cycle figure appears only on the bundle page and belongs to the separate B300K-for-Apex300 variant (see notes). |
| Attribute | Value |
|---|---|
| Charge temperature range | 0 °C to 40 °C (32 °F to 104 °F) |
| Discharge temperature range | -20 °C to 40 °C (-4 °F to 104 °F) |
| Attribute | Value |
|---|---|
| Weight | 29.5 kg (65.0 lb) |
| Dimensions (L × W × H) | 525 × 327 × 209 mm |
| Attribute | Value |
|---|---|
| Warranty | 3 years |
| Release status | Current |
| Market region | US |
Use cases
- Enlarging a BLUETTI AC200L, AC200MAX, AC300 or AC500 for longer outage or off-grid runtime
- AC500 or AC300 systems that need several stacked batteries for whole-day or multi-day backup
Strengths and weaknesses
Strengths
- Large 2,764.8 Wh LiFePO4 capacity in a single stackable unit
- Broadest host coverage here: four named AC-series stations
- Chemistry, capacity, weight and dimensions all published, with a manual PDF as a source
- A small 12 W USB-A trickle port for phones even when detached from a host
Weaknesses
- No AC output and no direct solar, car or AC charging: it must be recharged through a host
- How many units chain depends entirely on the host station (2 to 6)
- Name collides with a separate 'B300K for Apex300' SKU whose specs bleed onto the shared bundle page
- 29.5 kg: a heavy single-unit lift
Where to buy
Affiliate disclosure: some links below are affiliate links — if you buy through one we may earn a commission at no extra cost to you. This never affects which products are indexed, how they are ranked, or the specifications shown; those come from official manufacturer sources only. As an Amazon Associate I earn from qualifying purchases. Full disclosure.
| Merchant | Price | Checked | Availability | Link |
|---|---|---|---|---|
| BLUETTIprimaryManufacturer direct | Not tracked | — | — | View at BLUETTI |
| AmazonaffiliateMarketplace | Not tracked | — | — | View at Amazon |
Sources and provenance
Core specifications come from official manufacturer sources only, with the exact claim text preserved per field. Spec sheets and manuals outrank marketing copy. See the methodology for the full policy.
| Field | Normalized value | Raw claim | Source | Confidence |
|---|---|---|---|---|
chemistry | lifepo4 | LiFePO4 | Official product page | high |
capacityWh | 2764.8 | 2764.8Wh | Official product page — This unit's own energy (54 Ah x 51.2 V). Also printed on the product render's capacity badge. NOT a combined-system total. | high |
capacityAh | 54 | 54Ah | Official manual (PDF) | high |
nominalVoltageV | 51.2 | 51.2V | Official manual (PDF) — 54 Ah x 51.2 V = 2764.8 Wh, exactly matching the stated capacity. | high |
weightKg | 29.5 | — | Official manual (PDF) — Published weight 29.5 kg; sourced via research handoff (2026-08-15). This is the AC-series unit, not the 1.59 kg accessory whose weight bleeds onto the bundle page. | high |
dimensionsMm | [525,327,209] | — | Official manual (PDF) — 525 x 327 x 209 mm; sourced via research handoff (2026-08-15). | high |
officialCompatibilityStatement | Effortlessly integrates with BLUETTI AC200L, AC200MAX, AC300, and AC500 power stations | Effortlessly integrates with BLUETTI AC200L, AC200MAX, AC300, and AC500 power stations | Official product page — Four named AC-series hosts. Anchored on the canonical page, not the bundle page that adds Apex 300. | high |
compatibleHostModels | ["AC200L","AC200MAX","AC300","AC500"] | AC200L, AC200MAX, AC300, and AC500 | Official product page — Chain limits per host: AC200L 2, AC200MAX 2, AC300 4, AC500 6. | high |
ownOutletsNote | One USB-A, 12 W max (5 V / 2.4 A) | USB-A 12W | Official product page — The unit's only output port; visible on the product render. | high |
warrantyYears | 3 | 3+1 Years | Official product page — 3 years base plus 1 extended; recorded as 3. | high |
chargeTempRangeC | [0,40] | — | Official manual (PDF) — Charge 0 to 40 C, discharge -20 to 40 C; sourced via research handoff (2026-08-15). | high |