The RB50-HP is a 12V 50Ah lithium marine battery in RELiON’s High Performance series. This lithium iron phosphate battery is specially designed to handle both starting and cycling. It delivers powerful cranking amperage for easy starting, and low amp draw service for reliable auxiliary power. RELiON’s HP Series dual purpose batteries are a perfect compromise between the unique demands of starting service and deep cycling, low amp draw service.

The RB50-HP offers abundant power in a small footprint. It’s versatile and compact enough to be used in many marine applications including smaller boats with lower battery requirements, boats that require two of the same batteries and boats with electrical systems designed for just one battery.

The RB50-HP features installation flexibility and no maintenance over the life of the battery. It maintains consistent power and is equipped with an M8 terminal type and a built-in battery management system (BMS).


Ed P.

It’s amazing how long you can run the energy hog sonar units. I run the electronic for two days straight and still have 50% of batteries left. This gives me a peace of mind not have to turn off the units to save energy to get through the day.

Robert M.

So far I've been happy with it. I have it on my boat to use for starting an outboard engine. It performed very well. I'm still on an early stage so hopefully, it will perform as expected in a year down the road.



Electrical Specifications

Nominal Voltage 12.8V
Nominal Capacity 50Ah
Capacity @ 25A 120 min
Energy 640 Wh
Resistance ≤20 mΩ @ 50% SOC
Efficiency 99%
Self Discharge <3% per Month
Maximum Modules in Series 1 (Single Use)

Mechanical Specifications

Dimensions (L x W x H) 10.2 x 6.6 x 8.6” 260 x 168 x 218 mm
Weight 18.7 lbs (8.5 kg)
Terminal Type M8 x 1.25
Terminal Torque 80 - 100 in-lbs (9 - 11 N-m)
Case Material ABS
Enclosure Protection IP66
Cell Type - Chemistry Cylindrical - LiFePO4

Discharge Specifications

Maximum Continuous Discharge Current 50 A
Peak Discharge Current 400 A (≤3 s)
BMS Discharge Current Cut-Off 550 A ±60 A (42 ±22 ms)
Recommended Low Voltage Disconnect 11V
BMS Discharge Voltage Cut-Off 8V (2.0 ±0.08 vpc) (100 ±50 ms)
Reconnect Voltage 10V (2.5 ±0.1 vpc)
Short Circuit Protection 200-800 μs

Charge Specifications

Recommended Charge Current 2.5 A - 25 A
Maximum Charge Current 50 A
Recommended Charge Voltage 14.2V - 14.6V
Charge Current 32º to 14ºF (0 to -10 ºC) ≤0.1 C
Charge Current -4º to 14ºF (-20 to -10 ºC) ≤0.05 C
BMS Charge Voltage Cut-Off 15.2V (3.8 ±0.05 vpc) (1.0 ±0.5 s)
Reconnect Voltage 14.4V (3.6 ±0.05 vpc)
Balancing Voltage 14.4V (3.6 ±0.025 vpc)

Temperature Specifications

Discharge Temperature -4 to 140 ºF (-20 to 60 ºC)
Charge Temperature* -4 to 113 ºF (-20 to 45 ºC)
Storage Temperature 23 to 95 ºF (-5 to 35 ºC)
BMS High Temperature Cut-Off 185 ºF ±5 ºF (85 ºC ±5 ºC)
Reconnect Temperature 140 ºF ±59 ºF (60 ºC ±15 ºC)
*Refer to charge currents below 0°C (32°F)

Compliance Specifications

Certifications CE (battery) UL1642 & IEC62133 (cells)
Shipping Classification UN 3480, CLASS 9

Performance Characteristics


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