LiFePO4 Batteries for Marine Applications |
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LiFePO4 Battery Showing Cells and BMS Electronics
LiFePO4 (lithium iron phosphate) is a lithium-ion battery technology that is safe, powerful and plug compatible with most lead acid battery charging systems. This battery technology offers many advantages over lead acid technology including high capacity storage, delivery of consistent high power, longer cycle life, less weight, longer shelf life and rapid charging.
LiFePO4 batteries are the safest type of Lithium batteries as they will not overheat, and even if punctured they will not catch on fire. The cathode material in LiFePO4 batteries is not hazardous, and thus poses no negative health hazards or environmental hazards. Most LiFePO4 batteries are plug compatible with lead acid batteries and will accept a charge from most lead acid configured chargers.
A LiFePO4 battery has two primary components, the LiFePO cells and the Battery Management System (BMS). The quality of each component is key to the longevity and performance of the battery. A number of cells are wired in parallel to form a module producing 3.2 volts. Four of these units are connected together in series to form a rated 12.8 volt LiFePO4 battery. The heat, charge and discharge of each cell is managed by the BMS, a computer built into each battery. A common LiFePO4 battery is rated at 100 amp hours and is roughly the size of a group 31 lead acid battery. These batteries are also rated as to their maximum discharge capacity. 100 Amps max discharge is common. We prefer a higher maximum discharge rate of 150 Amps for marine applications for both house and start power.
LiFePO4 batteries are the safest type of Lithium batteries as they will not overheat, and even if punctured they will not catch on fire. The cathode material in LiFePO4 batteries is not hazardous, and thus poses no negative health hazards or environmental hazards. Most LiFePO4 batteries are plug compatible with lead acid batteries and will accept a charge from most lead acid configured chargers.
A LiFePO4 battery has two primary components, the LiFePO cells and the Battery Management System (BMS). The quality of each component is key to the longevity and performance of the battery. A number of cells are wired in parallel to form a module producing 3.2 volts. Four of these units are connected together in series to form a rated 12.8 volt LiFePO4 battery. The heat, charge and discharge of each cell is managed by the BMS, a computer built into each battery. A common LiFePO4 battery is rated at 100 amp hours and is roughly the size of a group 31 lead acid battery. These batteries are also rated as to their maximum discharge capacity. 100 Amps max discharge is common. We prefer a higher maximum discharge rate of 150 Amps for marine applications for both house and start power.
Advantages and Features of Our LiFePO4 Marine Batteries
Charge/discharge cycles - LifePO4 batteries have an expected life of 2,000-4,000 charge/discharge cycles at a discharge to 90%. Lead acid batteries have an expected life of 300-700 charge/discharge cycles at a discharge to 50%.
Discharge profile - LifePO4 batteries stay at a voltage of 13 to 13.4 volts during discharge of up to a 95+%. Voltage then drops off rapidly. A lead acid battery decreases in voltage from 13 to below 12 volts as more current is drawn. This means many appliances will operate more efficiently throughout the discharge cycle using LiFePO4 batteries.
Discharge rate - The BMS built into our batteries has a 150 amp discharge capacity. This means the batteries can sustain a heavy discharge without damage or degradation. Our manufacturer has advised us that the quality of the cells and quality of the BMS is key to the longevity and performance of a LiFePo4 battery. We have seen this firsthand.
Charge/discharge cycles - LifePO4 batteries have an expected life of 2,000-4,000 charge/discharge cycles at a discharge to 90%. Lead acid batteries have an expected life of 300-700 charge/discharge cycles at a discharge to 50%.
Discharge profile - LifePO4 batteries stay at a voltage of 13 to 13.4 volts during discharge of up to a 95+%. Voltage then drops off rapidly. A lead acid battery decreases in voltage from 13 to below 12 volts as more current is drawn. This means many appliances will operate more efficiently throughout the discharge cycle using LiFePO4 batteries.
Discharge rate - The BMS built into our batteries has a 150 amp discharge capacity. This means the batteries can sustain a heavy discharge without damage or degradation. Our manufacturer has advised us that the quality of the cells and quality of the BMS is key to the longevity and performance of a LiFePo4 battery. We have seen this firsthand.
"C" is the rated Amp Hour BMS Discharge Capacity (150 Amps)
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Charge and Cycle Curves
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Smartphone app for LiFePO4 Battery Monitoring
Weight/power ratio - A typical 100 Ah LiFePO4 battery weighs about 31 pounds. A comparable lead acid battery is over twice that. Because LiFePO4 batteries can be safely be drawn down 90% vs 50%-60% for lead acid, fewer batteries are required to achieve the same power. Battery weight combined with useful power capacity means battery weight can be cut by more than half using LiFePO4 batteries. Also, LiFePo4 batteries will occupy up to 40% less space than equivalent lead acid batteries.
For example, 3 group 31 110 amp hour lead acid batteries weighing a total of 200 pounds can be replaced by 2 group 31 size 100 amp hour LiFePO4 batteries weighing a total of 62 pounds. Both configurations have roughly the same power capacity because the lead acid can be safely drawn down 50% (330 amps @50% = 165 amps) and the LiFePO4 can be safely drawn down 90% (200 amps @ 90% = 180 amps). Also, the lead acid will endure 400-600 cycles and the LiFePO4 over 2,000 cycles.
Example: Lead Acid LiFePO4
Battery Bank 3 Group 31 110 Ah 2 Group 31 size 100 Ah
Rated Capacity 330 Amps 200 Amps
Useable Capacity 165 Amps 180 Amps
Charge/discharge cycles 400-600 2,000-4,000
Weight 200 pounds 62 pounds
Safety - Li batteries have a reputation for catching fire. Not so with LiFePO4, a very different technology. The built in Battery Management System (BMS) monitors the state of charge of each cell group and manages the charge and discharge rates. These batteries have two major components, the LiFePO (Lithium Iron Phosphate) cells and the BMS (computer). The components are housed in a sealed battery case. There are no toxic chemicals or gases as in many types of lead acid batteries. The batteries can be mounted in any direction; bottom or side.
Compatibility - While the optimal charging parameters vary between LiFePO4 and lead acid battery technology, the BMS built into our LiFePO4 batteries compensates for this. Thus, our LiFePO4 batteries are compatible with most lead acid battery charging systems.
Battery Monitoring - Our LiFePO4 batteries are equipped with two methods of monitoring battery State of Charge (SOC). This is important because unlike lead acid batteries, LiFePO4 batteries maintain a constant voltage between 13 and 13.4 volts so a volt meter is not a good indication of SOC. A four light LED meter is built into the top of each battery to roughly indicate the SOC. A built in Bluetooth capability enables real time monitoring of each battery through an app on a smartphone. The app displays the state of charge of the battery, the amp draw and voltage level, the temperature, the time to full charge and the number of charge/discharge cycles. This capability is nearly equivalent to having a built in battery bank monitoring system like a Link 2000.
Winter Operation and Storage - LiFePO4 batteries can be stored in temperatures of -20°F (0°C). It is recommended they not be charged and discharged at temperature below 0°F (-20°C) For winter storage, it is recommended that the negative terminals be disconnected so there is no chance of draining the batteries while in storage.
Cost - LiFePO4 batteries are 2 to 5 times the cost of comparable lead acid type batteries. Cost justification has to be based on convenience, performance and longevity. Factors to consider in evaluating cost include the number of cycles, weight, charge and discharge parameters and compatibility.
Bottom line - Our LiFePO4 marine batteries are lighter, can be drawn down 90%, hold a steady voltage, are plug compatible with lead acid chargers, and charge more quickly than lead acid batteries. They are nontoxic and safe. They are more expensive than lead acid however their advantages often outweigh the additional expense.
For example, 3 group 31 110 amp hour lead acid batteries weighing a total of 200 pounds can be replaced by 2 group 31 size 100 amp hour LiFePO4 batteries weighing a total of 62 pounds. Both configurations have roughly the same power capacity because the lead acid can be safely drawn down 50% (330 amps @50% = 165 amps) and the LiFePO4 can be safely drawn down 90% (200 amps @ 90% = 180 amps). Also, the lead acid will endure 400-600 cycles and the LiFePO4 over 2,000 cycles.
Example: Lead Acid LiFePO4
Battery Bank 3 Group 31 110 Ah 2 Group 31 size 100 Ah
Rated Capacity 330 Amps 200 Amps
Useable Capacity 165 Amps 180 Amps
Charge/discharge cycles 400-600 2,000-4,000
Weight 200 pounds 62 pounds
Safety - Li batteries have a reputation for catching fire. Not so with LiFePO4, a very different technology. The built in Battery Management System (BMS) monitors the state of charge of each cell group and manages the charge and discharge rates. These batteries have two major components, the LiFePO (Lithium Iron Phosphate) cells and the BMS (computer). The components are housed in a sealed battery case. There are no toxic chemicals or gases as in many types of lead acid batteries. The batteries can be mounted in any direction; bottom or side.
Compatibility - While the optimal charging parameters vary between LiFePO4 and lead acid battery technology, the BMS built into our LiFePO4 batteries compensates for this. Thus, our LiFePO4 batteries are compatible with most lead acid battery charging systems.
Battery Monitoring - Our LiFePO4 batteries are equipped with two methods of monitoring battery State of Charge (SOC). This is important because unlike lead acid batteries, LiFePO4 batteries maintain a constant voltage between 13 and 13.4 volts so a volt meter is not a good indication of SOC. A four light LED meter is built into the top of each battery to roughly indicate the SOC. A built in Bluetooth capability enables real time monitoring of each battery through an app on a smartphone. The app displays the state of charge of the battery, the amp draw and voltage level, the temperature, the time to full charge and the number of charge/discharge cycles. This capability is nearly equivalent to having a built in battery bank monitoring system like a Link 2000.
Winter Operation and Storage - LiFePO4 batteries can be stored in temperatures of -20°F (0°C). It is recommended they not be charged and discharged at temperature below 0°F (-20°C) For winter storage, it is recommended that the negative terminals be disconnected so there is no chance of draining the batteries while in storage.
Cost - LiFePO4 batteries are 2 to 5 times the cost of comparable lead acid type batteries. Cost justification has to be based on convenience, performance and longevity. Factors to consider in evaluating cost include the number of cycles, weight, charge and discharge parameters and compatibility.
Bottom line - Our LiFePO4 marine batteries are lighter, can be drawn down 90%, hold a steady voltage, are plug compatible with lead acid chargers, and charge more quickly than lead acid batteries. They are nontoxic and safe. They are more expensive than lead acid however their advantages often outweigh the additional expense.
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Specifications
Electrical Characteristics Normal Voltage 12.8 Rated Capacity 100±3 Amp hrs (.2C) Energy 1280 Watt hrs Internal Resistance ≤40mOhms Cycle Life ≥2,000 @ 0.2C (100% Depth of Discharge DOD) ≥6,000 @ 0.2C (80% DOD) ≥10,000 @ 0.2C (50%DOD) Passive Protection Over charge, over discharge, temperature protection Standard Charge Charge Voltage 14.4±0.15 V Charge Mode 14.4 V Charge Current 30 Amps (.2C) Max. Charge Current 75 Amps (.5C) Standard Discharge Continuous Current 75 Amps (.5C) Max. Continuous Current ≤150 Amps (C) Discharge Cut-off Voltage 10.0 V Environmental Charge Temperature 32°F to 113°F 0°C to 45°C Discharge Temperature -4°F to 140°F -20°C to 60°C Storage Temperature -10°F to 104°F -25°C to 40°C Mechanical Material System LiFePO4 Material Case Plastic Dimensions 13.4 in x 6.8 in x 8.4 in H 342mm x 173mm x 212mm H Weight 31 lb. 14.2 Kg Terminal M8 State of Charge Bluetooth, LED/LCD |
LiFePO4 Marine Battery - 100 Ah 12.8 volt
$
899.00
These 100 Ah LiFePO4 batteries are designed for both house and start applications. They have a built in 150 amp Battery Management System and are plug compatible with most lead acid charging systems.