RB300 LiFePO4 Battery Gr 8D 12V 300Ah 0.3C
RELiON RB300 LiFePO4 Battery 12V 300Ah Group 8D — Large-Format Lithium Power for Marine, Solar & Commercial Applications
The RELiON RB300 is a Group 8D 12V 300Ah (3,840Wh) LiFePO4 (lithium iron phosphate) battery engineered for large-format energy storage applications requiring maximum capacity in a standard 8D footprint. At 3,840Wh of usable energy and a 0.3C continuous discharge rate, it is purpose-built for high-capacity marine house banks, large off-grid solar systems, commercial vehicle auxiliary power, and industrial standby applications where a direct 8D drop-in lithium upgrade is required.
Compared to an equivalent Group 8D AGM battery, the RB300 delivers significantly more usable energy (100% DoD vs. ~50% for AGM), longer cycle life (2000+ cycles vs. 300–500 for AGM), and dramatically less weight per usable kWh. Backed by an industry-leading 36-month full warranty with 10-year prorated coverage from RELiON.
Key Features
- 12V / 300Ah / 3,840Wh — maximum capacity Group 8D lithium cell for large-format energy storage
- Group 8D form factor — direct drop-in lithium replacement for standard 8D battery positions
- LiFePO4 chemistry — safest lithium chemistry; no thermal runaway risk; 2000+ cycle life
- 0.3C continuous discharge rate — 90A continuous discharge for sustained high-draw applications
- 100% usable depth of discharge (DoD) — full 300Ah available vs. ~150Ah usable from equivalent AGM
- Integrated BMS — protects against overcharge, over-discharge, short circuit, and temperature extremes
- Absorption voltage: 14.2–14.6V / Float voltage: 13.5V — for proper charging system configuration
- 36-month full warranty / 10-year prorated — industry-leading coverage from RELiON
Specifications
- Voltage: 12V (nominal)
- Capacity: 300Ah
- Energy: 3,840Wh
- Discharge Rate: 0.3C (90A continuous)
- Chemistry: LiFePO4 (Lithium Iron Phosphate)
- Group Size: 8D
- Absorption Voltage: 14.2–14.6V
- Float Voltage: 13.5V
- Dimensions: 20.6" x 10.5" x 8.7" (522 x 267 x 220 mm)
- Weight: 34.36 kg
- Colour: Blue
- Part/Model Number: RB300
- Brand: RELiON
- Warranty: 36 months full / 10 years prorated
Ideal For
- Large marine house battery banks and liveaboard vessels
- Off-grid and solar energy storage systems requiring high capacity
- Commercial vehicle and truck auxiliary power units (APUs)
- RV and motorhome large house battery banks
- Industrial and telecom standby power applications
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