12V 35Ah
Deep Cycle Lithium Battery


12V 35Ah
Deep Cycle Lithium Battery

Estimated 1 - 2 weeks shipping.

The RB35 lithium iron phosphate battery is powerful yet compact enough to fit many deep cycle applications. The RB35 is ideal for fishing electronics, robotics, solar lighting, remote power and outdoor adventures.

SAVE $38.49


MSRP: $384.95

United States Of America White 230216 103954


Warranty White 230216 103954


Free Delivery White 230216 103955




RELiON lithium batteries provide more power than lead-acid batteries and are typically half the weight. Boosting both performance and agility on the water.

More Usable Capacity

Lead-acid batteries are typically sized up to two times your energy needs to account for extended periods without sun and less usable energy with higher rates of discharge. Plus, you are typically cautioned to limit your use to 50% of the rated capacity, as using more can significantly reduce performance. Lithium batteries provide 100% of their rated capacity, regardless of the rate of discharge. And, you can use it all and still get substantially longer cycle life.

Long Life

RELiON lithium batteries provide up to 10 times longer life than lead-acid batteries, and they still provide 80% of the rated capacity after 3,500 cycles.

Fast Charging

RELiON lithium batteries charge much faster than traditional lead-acid batteries, and they’re packed with more usable energy and up to 10 times longer life so you’re always ready to go!

Partial State of Charge Tolerant

Partial state of charge, known as PSOC, which is a killer of lead-acid batteries, does not affect performance or battery life of a lithium battery. Sometimes batteries don’t get fully charged, or they regularly operate in a partial state of charge. Either way, you can count on RELiON lithium batteries living a long and productive life.

Temperature Tolerant

Lithium batteries can handle a wide variety of conditions and are even 2.5x more efficient at low temperatures than lead-acid while being able to safely operate up to 149°F (65°C).

Eco Friendly & Safe

RELiON lithium batteries are the ultimate clean energy. No gassing, no fumes, and no pollution. Enjoy reliable power, while protecting the environment, using these non-hazardous batteries.



Electrical Specifications

Nominal Voltage 12.8 V
Nominal Capacity 35 Ah
Capacity @ 25 A 84 min
Energy 448 Wh
Resistance ≤50 mΩ @ 50% SOC
Efficiency 99%
Self Discharge <3% per Month
Maximum Batteries Connected in Series 3

Mechanical Specifications

Dimensions (L x W x H) 7.8 x 5.2 x 6.7” (195 x 131 x 171 mm)
Weight 9.9 lbs (4.5 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 35 A
Peak Discharge Current 70 A (7.5 s ±2.5 s)
Discharge Over-Current Protection 170 A ±20 A (20 ±5 ms)
Recommended Low Voltage Disconnect 11.0 V
Discharge Under-Voltage Protection 8.0 V (2.0 ±0.08 vpc) (140 ±60 ms)
Reconnect Voltage 10.0 V (2.5 ±0.10 vpc)
Short Circuit Protection Response Time 200-600 µs

Charge Specifications

Recommended Charge Current 1.75 A - 17.5 A
Maximum Continuous Charge Current 35 A
Charge Current 32ºF to 14ºF (0 to -10 ºC) ≤0.1 C (3.5 A)
Charge Current -4ºF to 14ºF (-20 to -10 ºC) ≤0.05 C (1.75 A)
Recommended Charge Voltage 14.2 V - 14.6 V
BMS Charge Voltage Cut-Off 15.2 V (3.8 ±0.025 vpc)
(1.1 ±0.4 s)
Reconnect Voltage 14.4 V (3.6 ±0.050 vpc)
Balancing Voltage 14.4 V (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)
Recommended Storage Temperature 23 to 95 ºF (-5 to 35 ºC)
BMS High Temperature Cut-Off 176 ºF (80 ºC)
Reconnect Temperature 122 ºF (50 ºC)
*Refer to charge currents below 0°C (32°F)

Compliance Specifications

Certifications UKCA & CE (battery)
UN38.3 (battery)
UL1642 (cells) (File# MH64523)
IEC62133 (cells)
Shipping Classification UN 3480, CLASS 9

Performance Characteristics

Charge Voltage Char Chart 12 V graph
Charge Voltage Soc Chart 12 V graph
Discharge Voltage At Various Rates 12 V graph
Discharge Voltage Chart 12 V graph
Life Vs Lead Acid Chart graph
Cycle Life Vs Depth Discharge Chart graph


Paul H.

Using the RB35 to power a 100 watt amateur radio transceiver for portable operation. Gives me several hours of useful on-air time, and is light weight (approximately 10 pounds). Great application!

The RB35 Is Great For Powering

Solar 230216 114023

Renewable Energy

Anchor V2 230216 114031


Recreational 230216 114025


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