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RELiON RB100 LiFePO4 Lithium Iron Phosphate 12V Battery, Group 31

Original price $1,314.38 - Original price $1,314.38
Original price
$1,314.38
$1,314.38 - $1,314.38
Current price $1,314.38
Item locally warehoused

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

RELiON RB100 LiFePO4 lithium iron phosphate battery (12V, Group 31) is a maintenance-free deep-cycle power solution built for demanding life on land or water.

Key Features

  • LiFePO4 chemistry designed for reliable performance
  • Built-in battery management system (BMS) helps protect the battery during charging and use ([relionbattery.com](https://www.relionbattery.com/products/lithium/rb100?utm_source=openai))
  • More usable capacity—100% of rated capacity is available depending on the application and discharge profile ([westmarine.com](https://www.westmarine.com/relion-group-31-rb100-lithium-iron-phosphate-deep-cycle-battery-12v-100ah-20482972.html?utm_source=openai))
  • Longer cycle life—up to 10x longer than lead-acid, with 80% of rated capacity remaining after 2,000 cycles (as stated by RELiON) ([westmarine.com](https://www.westmarine.com/relion-group-31-rb100-lithium-iron-phosphate-deep-cycle-battery-12v-100ah-20482972.html?utm_source=openai))
  • Maintenance-free, “plug and play” operation (no watering) ([westmarine.com](https://www.westmarine.com/relion-group-31-rb100-lithium-iron-phosphate-deep-cycle-battery-12v-100ah-20482972.html?utm_source=openai))
  • Can be installed upright or on its side (installation flexibility)
  • Designed for safe operation with a case intended for marine-style conditions ([defender.com](https://defender.com/en_us/relion-rb100-deep-cycle-lithium-battery-group-31?utm_source=openai))

Intended Use

  • Marine deep-cycle applications (house batteries)
  • RV and off-grid power storage
  • Solar and renewable energy backup power

Product Details

  • RELiON RB100 LiFePO4 Lithium Iron Phosphate 12V Battery, Group 31
  • Battery type: LiFePO4 (Lithium Iron Phosphate) ([relionbattery.com](https://www.relionbattery.com/products/lithium/rb100?utm_source=openai))
  • Nominal voltage: 12.8V ([solar-electric.com](https://www.solar-electric.com/lib/wind-sun/Relion_RB100_Specifications.pdf?utm_source=openai))
  • Capacity: 100Ah ([solar-electric.com](https://www.solar-electric.com/lib/wind-sun/Relion_RB100_Specifications.pdf?utm_source=openai))
  • Energy: 1280Wh ([solar-electric.com](https://www.solar-electric.com/lib/wind-sun/Relion_RB100_Specifications.pdf?utm_source=openai))
  • BCI Group: 31 ([solar-electric.com](https://www.solar-electric.com/lib/wind-sun/Relion_RB100_Specifications.pdf?utm_source=openai))
  • Terminal: top-mounted ([boatplicity.com](https://boatplicity.com/16650344-relion-rb100?utm_source=openai))
  • Stud/terminal hardware: M8 threaded stud terminals ([boatplicity.com](https://boatplicity.com/16650344-relion-rb100?utm_source=openai))
  • Case/engineering: built with a battery management system (BMS) ([relionbattery.com](https://www.relionbattery.com/products/lithium/rb100?utm_source=openai))
  • Installation orientation: can be installed upright or on its side (as stated in provided description)

Parts Desk Insights

Best Use Case: A strong choice when you want a lightweight, maintenance-free Group 31 replacement battery for marine or RV power systems that benefit from deep-cycle use.

Common Issues: If you’re upgrading from lead-acid, confirm your charger profile is compatible with LiFePO4 charging. Also verify terminal location and polarity orientation in your battery compartment to ensure clean cable routing for top-mounted terminals.

Related Products & Accessories

  • Battery Chargers & Accessories (category) - Browse the relevant Batteries/Charging accessories category to match your charger and connection needs.
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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