LiFePO4 batteries on boats and yachts - properties, special features and use

LiFePO4 batteries, also known as lithium iron phosphate batteries, are rechargeable lithium-ion batteries. The name comes from the abbreviations of the chemical elements lithium (Li), iron (Fe) and phosphate (PO4). These batteries offer long life, high energy density, improved discharge and charge efficiency and the ability to handle high charge and discharge rates. LiFePO4 batteries are a better option than other lithium-ion batteries due to their chemical stability and environmental friendliness. These properties make LiFePO4 batteries the preferred choice for use on boats and yachts.

LiFePO4 batteries can reliably supply on-board lighting, navigation instruments and other electronic devices on board with power. Furthermore, they can be charged with renewable energy sources such as wind or solar systems on sailing boats.

It is not recommended to combine LiFePO4 batteries with other types such as lead-acid or AGM batteries in series or in parallel. Generally speaking, these batteries have different discharge currents and charging methods.
But that doesn't mean you can't use different types of battery for different purposes on board. For example, a lead-acid or AGM battery works well as a starter battery, while a LiFePO4 battery can be used to power your devices and appliances.

LiFePO4 batteries of the same type and capacity can be connected together. There are two methods for combining LiFePO4 batteries:

Parallel connection: Combining batteries in parallel is done by connecting positive to positive and negative to negative in order to increase the total capacity while keeping the voltage constant. It is important to ensure that all batteries have the same state of charge to avoid imbalances.

Series connection: This is where the batteries are connected positive to negative in order to increase the overall voltage. It is important that all batteries have the same internal resistance and capacity to ensure that the voltage is balanced and to avoid potential risks of overcharging or deep discharge.

However, please note the following:

Balancing: It is particularly important to ensure that all batteries are charged and discharged evenly when connected in series. This can be done using a battery management system (BMS), which monitors the voltage and charge level of each battery and regulates it accordingly.

Safety: When connecting several LiFePO4 batteries, it is important to observe safety measures to avoid short circuits and overheating. This includes using appropriate connection wires, insulation materials and protective devices such as fuses or protective circuits.

1. Only select batteries with the same voltage and capacity for a battery bank.
2. Only use suitable connecting cables and plugs to avoid loose connections.
3. A battery management system (BMS) for LiFePO4 batteries is essential.
4. The BMS should have cell balancing, temperature monitoring and protection functions. Operate the battery bank within the manufacturer's recommended temperature range.
5. Ensure that the battery bank is sufficiently ventilated.
6. Implement safety precautions such as overcurrent and short-circuit protection.
7. Make sure there is an emergency shut-off switch.

Yes, the ambient temperature can affect the performance of LiFePO4 batteries. It can have a significant impact, leading to a loss of capacity and increased internal resistance in the case of low temperatures, which limits performance and slows down charging and discharging. Furthermore, low temperatures can impair the fast- charging capability of LiFePO4 batteries, resulting in reduced charging speed or damage. Both high and low temperatures accelerate ageing processes, which shortens battery life. Extreme temperatures harbour safety risks such as overheating or thermal failures, especially if handled incorrectly. You can operate your batteries at a temperature between 0 and 45 °C, the optimum and recommended operating temperature range is between 5 and 35 °C.

No, you should not use lithium iron phosphate batteries as a starter battery for engines.

Using LiFePO4s as an energy source for electric boat motors is not recommended. High-performance lithium batteries are specially designed for powering electric motors.

You can expect more than 3000 charging cycles without loss of performance and 10 years of service life or longer if batteries are used correctly and in compliance with safety regulations, regular maintenance and together with a BMS.

You should consider the following points when installing LiFePO4 batteries:

1. The battery must be fixed or mounted securely in the boat.
2. Ensure sufficient air circulation is possible.
3. The contacts of the batteries must be protected.
4. Attach connection cables firmly.
5. Only use compatible wires and make sure they are the required thickness.
6. Equip or connect the battery to a battery management system (BMS).
7. A battery balancer should ideally be connected in series.
8. Verify that wires are not broken or too long.
9. Batteries should be installed in the boat in such a way that there is no imbalance.
10. There should be protection against splashing water.
11. Install the battery in a location where large temperature differences do not occur.

The easiest way to determine the energy requirements of all your devices and appliances on your boat, start by calculating the total wattage of all consumers. Here's an example of how to calculate it:

Let us assume you have the following devices: An autopilot system with 45 watts, a navigation system with 15 watts, a radar system with 10 watts, navigation lights with 30 watts and a refrigerator with 80 watts.
The total wattage here is: 45 + 15 + 10 + 30 + 80 = 180 watts
If we assume that the appliances are operated for an average of 10 hours (we assume that the refrigerator does not run for the entire day), then the total energy requirement would be 180 W x 10 hours = 1800 watt hours (Wh).

The following formula must be used to determine the number of amp hours:

Amp hour (Ah) = Wh (watt hours) ÷ U (voltage (V)

In this case, we calculate 1800 Wh ÷ 12 V = 150 Ah

The battery, which is required for all appliances on board, must therefore have a capacity of at least 150 amp hours. If we also factor in reserve capacity, it makes sense in this example to use a battery with a capacity of 12V and 200 Ah.

1. Use a fairly heavy gauge wire of good quality to avoid overheating and the risk of fire.
2. Ensure correct polarity when connecting the batteries and components to prevent damage.
3. Solder or wire the connections to ensure strength and efficiency.
4. Insulate all connections carefully to prevent short circuits and electrical interference.
5. Keep the wiring neat and well organised to facilitate maintenance and troubleshooting.
6. Follow the instructions and recommendations of the BMS for the wiring and configuration of the battery bank.

1. Use fuses with the correct current rating that are matched to the specific requirements of the LiFePO4 battery.
2. Place fuses at strategic points in the wiring to prevent short circuits and overcurrents.
3. Make sure you install overcurrent protection that switches off quickly in the event of an overload or short circuit to protect the battery and the system.
4. Integrate a BMS that offers protective functions such as over-discharge and deep-discharge protection, temperature monitoring and cell balancing.

Protection from water: The battery should be installed on board the boat so as to avoid direct contact with water.
Sufficient ventilation: Make sure that there is sufficient ventilation to support heat dissipation and protect the battery from overheating
Stability: The battery must be securely fixed to prevent it from becoming dislodged when the vessel is moving.
Balance: Take care that multiple batteries are positioned in such a way that the weight of the batteries does not unbalance the boat.
Insulation: Avoid placing near materials that are highly flammable.
Electrical connections: The electrical connections should be properly insulated and protected from moisture.

Batteries should be positioned so that the boat is balanced. The best position for the batteries is the centre of the boat along the longitudinal axis. LiFePO4 batteries are significantly lighter than other batteries such as lead-acid batteries, so be aware of the difference in weight when replacing heavier lead-acid batteries with LiFePO4 batteries. You may need to adjust the positioning of your batteries to compensate.

Housing and sealing: Use a robust housing for the battery and ensure that it is sealed against moisture to prevent water ingress.
Reduce vibrations: Place the battery in a vibration-absorbing material or use special brackets to reduce vibrations and prevent damage.
Temperature control: Ensure that the battery is operated in an area with stable temperatures to maximise service life and performance and avoid potential damage from extreme heat or cold.
Monitor moisture: Install moisture sensors to detect possible water ingress as soon as possible and take appropriate measures.
Regular inspection and maintenance: Regularly check the housing, sealing and condition of the battery for signs of moisture ingress or damage.

Temperature is a crucial factor when using LiFePO4 batteries. You should make sure the temperature range is between 0 and +45 °C when operating your battery and avoid using at temperatures outside this range at all costs. Charging is most effective at temperatures between 5 and 35 °C, whereby the ideal temperature range for charging the battery is between 20 and 30 °C, i.e. approximately at room temperature.

Temperature: Excessively high or low temperatures can impair the performance and service life of your batteries. The best operating temperature for LiFePO4 batteries is between 20 and 40 degrees Celsius.
Moisture: Damp environments can lead to corrosion and short circuits, which can impair the efficiency of the batteries. Protect batteries from moisture with waterproof housings or suitable seals.
Charging and discharging processes: The correct management of charging and discharging processes can have a significant impact on the service life and performance of the batteries. Excessive discharging or overloading should be avoided to prevent damage and maintain efficiency.
Maintenance: Regular maintenance and inspection is important in order to recognise and rectify potential problems before they occur. This includes checking the connections, cleaning the battery housing and monitoring the state of charge.
Overloading: Battery performance can also depend on how much load they are exposed to. Practising appropriate battery management that distributes loads evenly can improve efficiency and extend battery life.

Keep the following points in mind when maintaining and inspecting your LiFePO4 battery:
Charge status: Regularly check the charge status and ensure that the battery is not completely discharged to prevent deep discharge.
Long-term storage: For longer storage periods, check the battery every 4-6 months and recharge to around 50% if necessary to maintain the service life.
Ventilation and temperature: Ensure adequate ventilation and an appropriate operating temperature (optimum: between 5 and 35 °C) to prevent overheating and protect the battery.
Check the connections and cables: Regularly check connections and cables for damage and make sure they are correct to ensure safe operation.

If your battery performance is significantly reduced or fails, it could be deeply discharged. Lithium iron phosphate batteries are considered to be deeply discharged if they have been discharged below their minimum final discharge voltage. This is around 8 to 10 volts for a battery with an output of 12.8 volts.
If a deep discharge has occurred, the battery should be checked for external damage and signs of overheating. In the event of serious damage or doubts about safety, the battery should be checked by a specialist. If the battery appears to be undamaged on the outside and there are no other signs of irregularities, gently charging the battery with low current could potentially resolve the deep discharge. The charging current should be limited to approximately 0.1C to 0.3C, where "C" is the capacity of the battery in ampere-hours. A charging current of around 10 to 30 amps would be suitable for a 100 Ah battery, if 1C corresponds to a current of 100 amps. For a smaller battery with 50 Ah, a charging current of around 5 to 15 amps would be appropriate.

CAUTION: This procedure harbours risks and can lead to further damage to the battery or even to overheating, fire and explosion of the battery. SVB recommends that you do not charge deeply discharged batteries yourself, but have them checked by a specialist.

Overvoltage: This occurs when the voltage rises above the permissible limit value. It can damage the battery, shorten its life and cause safety risks such as overheating and even fires.
Undervoltage: This occurs when the voltage falls below the permissible limit value. It can impair the performance of the battery, lead to incomplete discharge and, in the worst case, permanently damage the battery.
Both can be controlled by a battery management system (BMS), which monitors the voltage and, if necessary, interrupts the charging or discharging process to prevent overvoltage or undervoltage. In addition, regular, independent checks of the battery and adherence to the correct charging and discharging processes can help to avoid these problems.

Premature failure of LiFePO4 batteries well before the end of their average service life can be caused by various faults:
Overcharging: Charging the battery beyond its maximum capacity for too long can lead to damage that shortens the service life and can even lead to thermal runaway, i.e. an uncontrolled increase in the temperature of the battery, which can result in a fire or explosion.
Overheating: High temperatures during the charging or discharging process can damage the battery cells and impair their performance, which can lead to premature failure.
Deep discharge: Fully discharging the battery below its recommended voltage limits can cause irreversible damage to the cells and shorten their service life.
Mechanical damage: Physical damage such as shocks, impacts or improper handling can affect the integrity of the battery cells and lead to premature failure.

Avoiding deep discharge: Deep discharge can shorten battery life. Keep the battery voltage above a certain minimum value to prevent damage. The battery should not fall below a charge level of 20%; in addition, the battery should not fall below a final discharge voltage of between 8 and 10 volts for a 12.8 volt battery.
Maintain correct operating temperature: Operate the battery within a temperature range of 5 and 35 °C to maximise its performance and service life. Extreme temperatures above 45 °C and below 0 °C can damage the battery.
Avoid overcharging: Do not overcharge the battery as this can lead to premature ageing. Use chargers and battery management systems that switch off the charging process once the battery is fully charged.
Maintain the optimum charging temperature: The optimum ambient temperature for charging LiFePO4 batteries is between 5 and 40 degrees Celsius. Charging at room temperature yields the best results. Extreme temperatures outside the range can impair charging efficiency and damage the battery.
If you use and charge the battery regularly, this can help it maintain optimum performance and capacity, as well as prolong its life.
Protection against physical damage: Avoid impacts, drops or other physical damage that could harm the battery cells.

The following are possible signs of a defective or damaged battery:
Reduced performance: When batteries do not provide the expected performance and last for a much shorter time than before, this could be an indication of a defect
Fast discharge:Sudden and unexpected discharge of the battery, in particular with normal use, can be an indication of defect.
Battery is warmer than usual: If batteries get extremely hot when charging or discharging, this could be a sign of malfunction.
Physical damage:Visible damage such as dents, cracks, melted areas on the plastic housing, expansion of the battery casing may indicate internal problems and a defect.
Marks on metal parts: Encrustations or discolouring on metal parts of the battery can be an indication of damage or defects.
Malfunctions during use: Sudden shutdowns or restarts may be a sign of a battery fault.

In general, lithium-ion batteries are considered dangerous goods during transport; this notwithstanding, damaged or defective lithium-ion batteries should be handled with particular care.
For transport, the batteries are assigned to category UN3480, class 9, packing group II. The relevant regulations must be followed during transport. This means that they must be packed in accordance with packing instruction P903 for transport by land or water (ADR, RID & IMDG) and packing instruction P965 for transport by air (IATA). The original packaging usually meets these requirements.
Caution: Wearing safety goggles, protective gloves and, if necessary, protective clothing is recommended when removing and transporting defective or damaged lithium-ion batteries.

LiFePO4 batteries that are at the end of their service life must not be disposed of with normal household waste. They must be disposed of properly. Companies that sell batteries or devices with integrated batteries are obliged to take back used batteries at the end of their service life and have them disposed of properly by an authorised waste disposal company. Vendors are not obliged to take back damaged or defective rechargeable batteries and batteries. You can find all the information you need about environmentally friendly disposal at SVB.

The battery management system (BMS) of a LiFePO4 battery is an electronic control unit that serves to optimise the performance, safety and service life of the battery. It monitors and regulates parameters while the battery is being charged and used.
The main tasks of the BMS include:
Cell monitoring: The BMS monitors the voltage of each individual cell in the battery, to check it is within a safe range. This prevents overloading or deep discharging of cells.
Temperature monitoring: It monitors the temperature of the battery and regulates if necessary the charging and discharging, in order to prevent overheating and to prolong battery life.
Cell balancing: The BMS balances out charging between cells, in order to guarantee that all cells are charged equally. This helps maximise battery life and optimise performance.
Protection function: It includes protective functions such as overheating protection, under voltage protection and over voltage protection to prevent damage to batteries and safety risks.
Some LiFePO4 batteries offer the option of connecting the BMS to a mobile phone app via an interface (e.g. Bluetooth) and thus being able to view the most important data on the status of a battery via the app. LiFePO4 batteries that have such an interface are usually labelled accordingly.

You can tell whether a LiFePO4 battery has an integrated BMS by the following indicators:
Connections and sensors: Batteries with integrated BMS systems may have additional connections or sensors that can serve as interfaces and connection points for communication and monitoring with the BMS. These can be recognised by switches, connection points and digital or other display elements.
Labels: Many batteries are labelled with stickers or markings that indicate a BMS. Labelling such as "BMS inside" or similar information indicates an integrated BMS.
Manufacturer information: The product description in the packaging or the technical specifications of the battery provided by the manufacturer should give information about an integrated BMS.

A BMS monitors various factors relevant to the functionality of the LiFePO4 battery in order to guarantee and optimise the performance, safety and service life of the battery. The most important monitored parameters are:
Battery temperature:The BMS measures the temperature of the battery to prevent overheating, as this can affect the performance and service life of the battery.
State of charge:It monitors the current charge level of the battery (also known as "State of Charge", abbreviated to "SOC") to ensure that the battery is not overcharged or deeply discharged.
Charging and discharging current: The BMS measures the current flow during charging and discharging to ensure that the battery is operated within safe limits.
Cell voltage: It monitors the voltage of each individual cell to ensure even charging and discharging and to detect cell imbalances.
Cycle count: The BMS also counts the number of charge and discharge cycles to monitor the service life of the battery and assess its condition.
Self-discharge: The self- discharge rate of the battery is also monitored by the BMS in order to minimise unwanted energy loss. If necessary, the BMS switches to protection mode.
This information is interpreted by comparing it with predefined limit values and algorithms in the BMS. Depending on the measured values, the BMS can take measures such as adjusting the charging current, switching off in the event of overheating or compensating for cell imbalances in order to protect the battery and optimise its performance.

Unbalanced cell voltages: If the battery management system (BMS) is not working properly, individual cells in the battery may have different voltages. For example, one cell could have a much lower voltage than the others, which could indicate a malfunction of the BMS.
Malfunction during charging or discharging: A defective BMS can result in the battery not being charged or discharged properly. This can manifest itself in unusually rapid discharging or overheating during the charging process.
Loss of battery performance or capacity: A defective BMS can lead to a loss of battery performance or capacity as it no longer monitors and controls the cells efficiently. If the battery suddenly delivers less power or its capacity decreases, this could indicate a BMS problem.
Modern lithium battery systems usually feature diagnostic functions that display error messages or warning lights if the BMS detects an internal problem. For example, an error message on the battery system display or a warning light may indicate that there is a fault within the BMS.

The sleep mode of the battery management system of a LiFePO4 battery is an automatic switch-off mechanism that is activated by the BMS to protect the battery from deep discharge or other damaging effects. If the battery is not used for a longer period of time or the charge is at a low level, the BMS can activate sleep mode to conserve the battery and extend its life. In sleep mode, the BMS continues to monitor the battery parameters, but switches off the current flow and reduces energy consumption to a minimum.

Regular monitoring: Do not leave batteries charging unattended to ensure that problems and irregularities can be recognised at an early stage.
Avoid overheating: Ensure an optimum ambient temperature of between 10°C and 40°C during the charging process.
Appropriate charger: Only use chargers with a built-in protection mechanism.
Avoid deep discharge: Charge batteries in good time after use to prevent deep discharge.
BMS protection: Make sure you have a battery management system (BMS) to protect the battery from overcharging and overheating.

LiFePO4 batteries can reach 3000 charging cycles before their performance decreases significantly. A charging cycle refers to a complete charge of the battery from empty to full, regardless of whether this is done in a single charging process or several partial charges.

LiFePO4 batteries should only be charged with a charger that is specially designed for charging lithium-ion batteries. Using a normal charger can lead to overcharging, undercharging or even damage to the battery. It is therefore advisable to use a charger that is suitable for the specific battery type to ensure a longer battery life and optimum performance.

Yes, LiFePO4 batteries on board a boat can be charged using solar or wind power. However a number of technical requirements are needed such as a charge regulator and BMS that are connected between the battery and solar/wind device that control and monitor the power feed into the batteries.

The initial charging of LiFePO4 batteries is the first charging cycle after manufacture or after a long period of non-use. The cells reach their optimum capacity and the electrolyte stabilises to maximise performance and service life. Fully charging before first use is essential to activate the maximum capacity and prepare the battery for use. Make sure you follow the manufacturer's instructions.

Charging LiFePO4 batteries varies depending on the capacity and charging current. For a LiFePo4 battery with 12 volts and 100 Ah, which is 50% discharged, the charging time is around one hour if it is charged with a charging current of 1C. This means that the charging current is equal to the nominal capacity of the battery. For a 100 Ah battery, this means that it can be fully charged within one hour with a charging current of 100 amps. "1C" is a unit of measurement for the charging current at which the battery is fully charged in one hour. So if a battery is charged with a charging current of 1C, this means that the charging current is equal to the nominal capacity of the battery.

Excessive discharge: LiFePO4 batteries should never be discharged below their minimum voltage to avoid damage.
Use of unsuitable chargers: It is important to use chargers that are specifically designed for LiFePO4 batteries to prevent overcharging or undercharging.
Overheating during charging: LiFePO4 batteries should be charged in well-ventilated areas to avoid overheating. Direct sunlight should also be avoided.
Unattended charging: LiFePO4 batteries should not be charged unattended to ensure that problems and irregularities can be recognised at an early stage.

Deep discharge: If the battery has been heavily discharged, this can activate a protective mechanism that prevents charging.
Damage to the cells: Physical damage or defects in the battery cells can prevent charging. This damage can be caused by improper handling, overheating or ageing.
Excessive temperatures: Excessive heating of the charger or the battery can impair the charging efficiency of the battery. To prevent overheating, it is advisable to charge the battery in a well-ventilated area and protect it from direct sunlight or heat sources.
Battery protection mechanism: If the battery protection mechanism of the battery is activated, it may not be possible to charge the battery. The BMS monitors the condition of the battery and can stop battery operation in the event of irregularities or malfunctions to prevent more serious damage and ensure safety.
Faulty charger or charger cable:A faulty charger or charger cable may prevent the battery from being charged. Check both for functionality and compatibility with the battery.
Ageing: Over time, LiFePO4 batteries lose power and their ability to store energy may decrease. This can also lead to the battery no longer charging properly.

The compatibility of the existing charge current distribution should be checked when converting to LiFePO4 batteries. In many cases, existing systems such as battery changeover switches, charge relays and isolating diodes can be used with LiFePO4 batteries. Nevertheless, it is important to compare the technical specifications and protective functions of the batteries with the system requirements, and to seek information from the manufacturer or expert advice if in doubt.

There are charging relays specially designed for LiFePO4 batteries. These relays are designed to meet the specific charging requirements of LiFePO4 batteries. They can charge the batteries efficiently and safely, for example by ensuring the correct charge voltage and current. When purchasing a charging relay for LiFePO4 batteries, it is advisable to check the manufacturer's specifications to ensure optimum compatibility and performance.

Avoid deep discharge: Deep discharging can damage the battery cells and shorten their life. It is advisable not to discharge the battery below a certain deep discharge level specified by the manufacturer.
Note the discharge capacity: The maximum discharge capacity of the battery should not be exceeded to avoid overheating and damage. The specified values can be found in the manufacturer's technical data.
Observe temperature range: The battery should be operated within the temperature range recommended by the manufacturer. Extreme temperatures can affect battery performance and shorten battery life.
Continuous monitoring: A battery management system (BMS) can be helpful in monitoring the battery's state of discharge, cell voltages and temperature.
Uniform discharge: When several batteries are connected in parallel in a bank, it is important that all the batteries are discharged uniformly to avoid over-discharging a single battery.
Take safety precautions: It is important to take safety precautions such as over-current protection and deep discharge protection to protect the battery and the connected system.

The possible discharge current of a LiFePO4 battery varies depending on the manufacturer and model of the battery. In general, compared to other battery types, LiFePO4 batteries can offer a high discharge current. Typically, LiFePO4 batteries can achieve discharge currents from 1C up to 3C or even higher, where "C" represents the capacity of the battery in Ah.
For example, a 100 Ah LiFePO4 battery can deliver a discharge current of 100 A to 300 A or more, depending on the manufacturer's specifications and the operating conditions. It is important to follow the manufacturer's specific instructions and to operate the battery within the recommended limits to avoid compromising performance and life.

The use of a LiFePO4 battery may affect the deep discharge protection of equipment such as refrigerators, as these batteries have a flat discharge curve, meaning that their voltage remains stable during discharge. This can strain conventional protection mechanisms, which are often based on a voltage threshold. In such cases, the threshold may need to be adjusted to ensure that the battery is not discharged below a critical state of charge.
For example: A cooling unit configured for conventional lead-acid batteries with a deep discharge protection threshold of 10.5V may need to adjust this threshold when using a LiFePO4 battery. As the LiFePO4 battery offers a more stable voltage, the protection threshold could be raised to 12V, for example, to provide a safer deep discharge protection function.

In principle, the state of charge of a LiFePO4 battery can be determined by measuring the voltage. However, it is not recommended to rely solely on the data collected during a voltage measurement, as the results may not always be accurate, especially when the battery is under load. It is therefore recommended to use a battery management system (BMS), for example, to obtain data on the state of charge.

Measuring the voltage alone to determine the state of charge of a LiFePO4 battery can be misleading as it is affected by many factors. This means that the battery voltage can drop under load even though the battery is still charged. The temperature can also change the voltage, whereby low temperatures can lead to higher voltages and vice versa. In addition, the battery can lose capacity over time, which also affects the voltage. Changes in internal resistance and short-term voltage fluctuations during charging and discharging can also affect the measured voltage. A Battery Management System (BMS) provides more accurate monitoring by taking into account additional parameters such as current, temperature and cell voltage. It enables more accurate determination of the state of charge and activates protection mechanisms against overcharging or deep discharging.

There are several ways to monitor the state of charge of a LiFePO4 battery, each requiring different equipment:

Voltage measurement:
Functionality:The battery voltage is measured to determine the state of charge. A typical final charge voltage for a fully charged LiFePO4 battery is around 3.65 to 3.8 volts per cell. The voltage measurement is a rough estimate of state of charge and can be inaccurate with temperature fluctuations or when under load.
Accuracy:Medium
Device: Multimeter or voltage gauge

Power measurement:
Function: The incoming and outgoing current of the batteries is measured to determine the current state of charge. The current measurement is very accurate and provides a direct insight into the current state of charge of the battery.
Accuracy: High
Device: Current measuring device or shunt

Battery management system (BMS):
Functionality:A BMS provides comprehensive monitoring of the battery status and takes into account parameters such as voltage, current, temperature and cell voltage. It can determine the state of charge more precisely and activate protective mechanisms to prevent overcharging or deep discharging. It combines multiple parameters, protecting the battery from potentially damaging conditions and providing comprehensive and accurate monitoring of battery health.
Accuracy: High
Device: BMS system

A shunt ensures a continuous overview of the technical data and the status of the LiFePO4 battery. The shunt is connected to the battery and creates a small voltage drop that is measured and interpreted to gather important data such as battery state of charge and performance. The use of a shunt is always advisable when a LiFePO4 battery does not have an integrated all-in-one BMS that can also monitor battery data.