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RELiON RB300 LiFePO4 Lithium Iron Phosphate 12V Battery, Group 8D

Original price $3,651.07 - Original price $3,651.07
Original price
$3,651.07
$3,651.07 - $3,651.07
Current price $3,651.07
Item locally warehoused

Free returns on all eligible orders

You have 30 days to request a return. All sale items are final sale.

The RELiON RB300 LiFePO4 lithium iron phosphate 12V battery (Group 8D) is a high-capacity deep-cycle power solution engineered for demanding life on land or water. With a LiFePO4 chemistry and built-in battery management, it’s designed for long service life, full usable capacity, and reliable performance.

Key Features

  • LiFePO4 lithium iron phosphate deep-cycle battery for 12V systems
  • Designed for deep-cycle use with constant power available throughout discharge
  • Lightweight alternative to lead-acid (50–60% less weight than lead-acid equivalent)
  • Maintenance-free operation—plug, play, and charge (no watering)
  • Engineered for safe storage and performance in harsh conditions
  • Operational temperature tolerance up to 149°F (65°C)
  • Can be installed upright or on its side

Intended Use

  • Marine (life on the water / deep-cycle battery banks)
  • RV and recreational vehicles
  • Solar and off-grid energy systems
  • Land-based power backup and accessory loads

Product Details

  • Brand/Series: RELiON RB300 (LiFePO4 Lithium Iron Phosphate)
  • Nominal system voltage: 12V
  • Group size: 8D
  • Battery capacity: 300Ah
  • Nominal voltage: 12.8V
  • Energy: 3840Wh
  • Dimensions (L x W x H): 20.5 x 10.5 x 9.0 in (520 x 267 x 228 mm)
  • Weight: 83 lb (37.5 kg)
  • Terminal type: M8
  • Case material: ABS
  • Enclosure protection: IP56
  • Self-discharge: <3% per month
  • Recommended charge current: 50A
  • Maximum continuous discharge current: 100A
  • Peak discharge current: 200A (7.5s ±2.5s)
  • Recommended charge voltage: 14.2V–14.6V
  • Recommended low voltage disconnect: 11V
  • BMS high temperature cut-off: 176°F (80°C)
  • Certifications (battery/cells): CE (battery), UN38.3 (battery), UL1642 & IEC62133 (cells)

Parts Desk Insights

Best Use Case: Ideal for customers replacing heavy lead-acid deep-cycle banks with a compact, high-capacity LiFePO4 battery where long-cycle performance and maintenance-free operation are priorities.

Common Issues: For a smooth installation, confirm battery-to-battery and charger requirements for LiFePO4 (proper charge voltage/current), verify the M8 terminal connection hardware matches your cables, and reference the wiring/charging guidance for your system to prevent over/under-voltage conditions.

Related Products & Accessories

Shipping information

In-stock and OEM parts: ship same or next business day.

Locally warehoused items: ship within 1-3 business days.

Special-order items: timeline confirmed after order.

Returns & warranty

Returns & Satisfaction Guarantee

We stand firmly behind the quality of every product we sell. Your confidence matters to us — and we back it with a straightforward 30-Day Satisfaction Guarantee.

If you are not fully satisfied, you may request a return within 30 days of delivery. All returns must receive pre-approval prior to being sent back. Unauthorized returns will not be accepted.

To qualify for a return:


  • Item must be in new, unused condition

  • Product must be in its original packaging

  • All parts, components, hardware, manuals, and accessories must be included

  • Packaging must be undamaged and suitable for resale

Important:

Electronics are strictly inspected. No returns on open-box electronics. Exceptions may apply only with prior written approval. Any electronic unit that has been installed, powered, activated, or altered may not be eligible for return.

We are serious about product integrity — and equally serious about taking care of our customers. If there is ever a product issue, contact us immediately so we can make it right.

For return authorization, please contact our support team before shipping anything back.

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