The car battery is the main part of the car that provides power to different components of the vehicle to perform different operations. Each vehicle comes with certain features for the battery and its voltage. Normally, a 12-volt battery is part of ICE cars for operating the lighting system and starting the car. While electric vehicles use high-voltage batteries, like 400 400volts or 800 volts. In this post, we will cover details about car battery volts and practical applications. So let’s get started.
Introduction to Car Battery Voltage?
- Car battery voltages are the potential difference between car battery terminals, measured in volts. The voltage of the car battery gives details about the charging level and battery health.
- Normally, a 12-volt lead-acid battery is used that comes with different charging levels.
Fully charged condition
- When the battery does not connect to the load and has a complete charging level, it comes with a voltage of about 12.6 to 12.8 volts.
Under Load state
- car engine in running condition, alternator providing charge to battery, and voltage level increases to 13.5 to 14.7 volts.
Partially Discharged
- In this level, battery voltages are 12.1 volts, which means fifty percent charging conditions, and if the 11.7-volt value is shown, it means the battery is 25% charged.
Fully Discharged:
- If the battery state is 10.5 or lower, that means it is in a completely discharged state.
Cranking Voltage:
- At car’s starting time, the voltage of the car reduces by about 10 volts since high current is required for the starting motor; that voltage is called cranking voltage
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CAR Battery Working
- The main purpose of any battery or car battery is to charge or store electrical energy. The starter transforms electrical energy into mechanical energy for the engine crank.
- When the engine starts, the alternator generates current that provides charging to the battery.
- These processes are continuous and give power to the engine when electrical energy is again transformed to mechanical, and the alternator provides current to the battery.
Importance of Car Battery Voltage
- Car battery voltage is important since it controls the working of the electrical system of the vehicle. If the voltage is at a very low level, the car will not start, and this will cause electrical faults.
- Some important factors of car battery voltage are as
Car starting process
- The main function of a car battery is to provide electrical power for engine starting. When we click the vehicle start button, power is given to the starting of the motor, and then the engine starts.
- If battery voltages are low, the required power is not delivered for engine starting.
Run electronic components.
- After the car engine starts, the battery gives power to the electrical system and related parts of the vehicle, like the dashboard, the AC system, and the lights.
- So if the battery has low voltage, it stops all electronic parts from working.
Battery charging
- • An alternator employs high voltage for car battery recharging when the engine is running. The accurate working of the alternator causes a smooth and full battery charging state. If the alternator or battery is not working well, the voltage reduces and causes the discharge of the battery.
Car Battery Types
12 volts is the standard voltage of a battery; different car battery types are used based on vehicle voltage requirements.
Lead-Acid Batteries
- This battery comes with lead plates dipped in sulfuric acid electrolyte. Lead and acid chemical reactions produce electrical energy.
- A lead-acid battery comes with low-cost features and is part of gasoline-operated vehicles. This battery needed electrolyte levels to be at a high level and cleaning to avoid corrosion.
Lithium-Ion Batteries
- These batteries come with lithium electrodes and an electrolyte. It comes with a higher energy density than lead-acid batteries.
- These batteries are commonly used in EVs and hybrid vehicles since they provide high power, low weight, and longer shelf life. It also has high-speed charging.
- It needed low maintenance but was affected by temperature, so it was charged through special tools.
Absorbent Glass Mat (AGM) Batteries
- This battery structure comes with a fiberglass mat dipped in electrolyte, which absorbs and stores potential through the mat. These features make the battery provide resistance to vibrations and have a spill-proof design.
- AGM batteries work well in high temperatures and harsh conditions. It is also part of a vehicle where a high-level electrical system is used.
- AGM battery needs low maintenance, and no electrolyte level checking is needed
Gel Cell Battery
- This battery comes with silica gel for the movement of electrolyte. so it is safe and durable. Gel cell battery performance is constant and has resistance for deep discharging. It is used for providing stable operations in RVs.
- These batteries also needed low maintenance.
Factors Affecting Car Battery Voltage
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Different factors are involved for car battery voltage. These factors help us to monitor battery health conditions and prevent different faults.
Battery age
- As a battery is used and becomes older, its charge reduces, which causes low voltage values. The battery’s normal working life is three to five years, and with time, its full charge maintenance features are affected. If you are facing lower car battery volts, replace it with a new one.
High/low Temperatures
- Either very low or very high temperatures affect the working of a car battery’s life. Very low temperature reduces battery power, and high temperature starts a chemical reaction in the battery that makes the battery’s life decrease fast.
- in low-temperature battery, power losses. Faulty cables cause slow cranking for car starting. High temperature also affects internal battery parts.
Loads on the battery
- If a car comes with different electrical parts like heated seats, a lighting system, and a high-end sound system, it puts high pressure on the battery and makes it discharge quickly.
- If the battery is facing high loads, it affects the voltage and causes early battery failure.
- To avoid battery failure to not use many electronic devices at the same time
Alternator faults
- The alternator generates power for the car’s running and battery recharging. If the alternator is not working, it will not provide the required battery recharging that loses voltage.
- If the alternator is not working well causes a voltage fault
How to check a car battery’s voltage?
Battery-accurate voltage level is important for the accurate working of the vehicle. different steps used for the accurate working of a car battery
Multimeter testing
- Test the battery with a multimeter for voltage calculation. for performing this test, first off, the car.
- Before measuring voltages, set dc voltage on the meter, then connect the red pin of the battery to the positive pin and the black to the negative pin. If the battery is completely charged, thecompletely charged, thecompletely charged, thecompletely charged, the reading will be 12.6 volts.
Use Battery Tester
- Battery testing is also used for measuring vehicle volts; tester clamps are connected with battery terminals for measuring volts.
- • The battery tester comes with a scale that gives an idea about battery health in good, fair, and poor conditions according to the voltage measured.
Voltage is measured when the engine is running.
- Calculate the voltage through the multimeter when the engine is started. During engine running, the battery voltage rating is between 13.7 and 14.7 volts. That means charging accurately
Car battery voltage chart
Here we have made a battery voltage chart for different types
| State of Charge | 12V Lead-Acid | 12V AGM | 12V Deep Cycle (Lead-Acid) | 12V LiFePO₄ | 12V Li-Ion | Detailed |
| 100% (Charging) | 14.4V | 14.6V | 13.0V | 14.6V | 13.6V | Charging voltage |
| 100% (Resting) | 12.7V | 12.8V+ | 12.8V | 13.6V | 13.6V | Fully charged |
| 90% | 12.5V | 12.7V | 12.75V | 13.3V | 13.4V | Excellent |
| 80% | 12.42V | 12.5V | 12.50V | 13.3V | 13.3V | Healthy |
| 70% | 12.32V | 12.35V | 12.30V | 13.2V | 13.2V | Normal |
| 60% | 12.20V | 12.15V | 12.15V | 13.1V | 13.1V | Acceptable |
| 50% | 12.06V | 12.05V | 12.05V | 13.0V | 13.0V | Recharge soon |
| 40% | 11.90V | 11.95V | 11.95V | 13.1V | 13.0V | Low |
| 30% | 11.75V | 11.81V | 11.81V | 13.0V | 12.9V | Very low |
| 20% | 11.58V | 11.66V | 11.66V | 12.9V | 12.8V | Critical |
| 10% | 11.31V | 11.51V | 11.51V | 12.0V | 12.0V | Damage risk |
| 0% | 10.5V | 10.5V | 10.5V | 10.0V | 10.0V | Fully discharged |
Different car battery voltages types
Commonly used car battery voltages are deep cycle, starter, and automotive. Each comes with certain features. The standard value of car battery’s volts is 12 volts. Some battery types based on voltage are as follows.
Golf cart batteries
- A standard golf car uses 4, 6, or 8 batteries that employ 36V or 48V batteries in a single configuration or casing.
Motorcycle battery
- The motorcycle battery uses a lithium-ion battery. Lithium-ion battery voltage value is 48v, 60v, or 72v. A proper working battery produces voltage in the required voltage.
Electric bicycle battery
- Electric bikes use 48-volt and 52-volt batteries. 52 volts is preferred since it has a longer working life and provides high power.
Drone battery
- Drones use lithium polymer batteries that charge at voltages of 4.2V, 8.4V, 12.6V, and 16.8V.
Trolling motor battery
- These batteries have 4 volt options: 12V, 24V, 12/24V, and 36 volts. A larger-size motor uses a larger voltage battery and produces faster rotation. that causes high power at the propeller shaft for high performance
Hybrid vehicles: Car battery voltage
- Hybrid vehicles come with an internal combustion engine with a motor that operates with a battery. The battery voltage of hybrid vehicles is less compared to that of electric vehicles.
Hybrid Vehicles Battery Voltages
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Mild hybrid electric vehicles
- Their voltage is 48 volts, and a common example is the Audi A6 55 TFSI e. These vehicles work with a 48-volt lithium-ion battery and ISG system. Low voltage minimizes the use of heavyweight insulation.
- 48-volt battery system compatible with ICE through providing start-stop working power and regenerative braking.
- It also provides fuel efficiency and minimizes emissions.
Full hybrid electric vehicles volts
- For these vehicles, the battery voltage range is 200 to 300 volts; an example is the Toyota Prius, the most well-known full hybrid.
- Complete hybrids use nickel metal hydride that stores high energy. This battery also reduces fuel use and reduces emissions more than mild hybrids. Their high-voltage maintenance keeps the operation of the motor compatible with ICE and electrical driving features.
Plug-in hybrid electric vehicles
- PHEVs use lithium-ion batteries with high capacity and require advanced charging and discharging cycles. Their voltage range is 300 to 400 volts; examples are the Chevrolet Volt and the BMW 330e.
- These vehicles use an onboard charger for managing the external input supply.
- PHEVs can cover longer distances with electrical power since they have high capacity and voltage.
How much life of a car battery
- Normally, a car battery’s working life is 2 to 3 years. If your car is not heavily used, it will have a working life of about 3 to 4 years. but the replaced battery life is about two years.
- Taxis’ or delivery vehicles’ battery life is hardly one year since the battery starts and stops.
Why 12 Volts battery commonly used
- A 12-volt system is standard in the vehicle industry since it has safe operation. Each vehicle uses six volts, but when components and power required increase, a 12-volt system is preferred. that provide high power without limiting the size of the battery
- A 12-volt system gives the required power to start the engine and power for different electronic parts of the vehicle, such as the radio, lights, and infotainment system. That voltage helps the vehicle operate effectively without overload.
- Some vehicle parts, like the starter and electronic control units, use 12 volts, so this system is preferred for vehicles. With that 12-volt system, it is easier to handle than high voltage. that has less chance of shock and does not need high maintenance
How many volts car battery has while running?
- When we start the car engine, the current needed for starting the engine varies according to temperature and altitude, so different voltages are needed according to todriving conditions.
- During running car battery voltage is in the range of 13.2-14.8 V. A fully charged battery range is is12.5v to 13v, and an uncharged battery voltage value is 12.4 volts for 75 percent charge.
- The 11.5 volts shows discharged battery voltage.
How many volts does a fully charged car battery have?
- 12.6 volts are for a fully charged car battery. The battery has 6 cells, each with 2.1 volts per cell. batteries connected in series, which increases the voltage for the charging vehicle.
- Fully charged batteries retain rated capacity without draining from charging conditions.
How many amps is a 12-volt car battery?
- Car batteries are 6 or 12 volts; a 12-volt battery produces 600 amps. Ampere is also the electricity volume that causes thatcausescurrent but voltage is called the “pressure” of the electricity.
How many amps and volts should a car battery have?
- A 12-volt car battery provides 30 to 50 amps and can also generate about 600 600amps. The average car battery capacity is 48 ampere hours; that shows a fully charged state and provides a single ampere for 48 hours.
