How A Car Battery Works - basic working principle
TLDRThe video script delves into the workings of the 12-volt lead acid car battery, an indispensable component in combustion engine vehicles. It explains that these batteries store chemical energy, which is converted into electrical energy when needed, and highlights their rechargeability. The script outlines the battery's role in starting the engine via the starter motor and how the alternator recharges the battery while the engine runs. It also details the battery's construction, including the lead plates, electrolyte, and the chemical reactions that occur within. The video further explores the fundamentals of electricity, including electron flow and conventional current theory, and explains the process of chemical reactions within the battery that enable it to provide power. The importance of maintaining the battery's charge and the consequences of deep or frequent discharges are also discussed. Finally, the script provides practical advice on testing the battery's voltage and encourages viewers to explore Squarespace for creating an online presence.
Takeaways
- π The 12-volt lead-acid car battery is a crucial component in every combustion engine vehicle, providing the necessary electrical energy to start the engine and power various electrical systems.
- π These batteries store energy in the form of chemical energy, which is converted into electrical energy when needed, and they are rechargeable by reversing the chemical reaction with an external electrical supply.
- ποΈ The battery is first used to start the engine by powering the starter motor, which engages a gear on the engine's flywheel, turning the crankshaft to initiate the combustion process.
- π The starter motor requires a large current, potentially hundreds of amps, for a short period, which can deplete the battery's energy storage, necessitating recharging by the engine's alternator.
- π The alternator, driven by the engine, generates electricity that is used to recharge the battery and power the car's electrical systems when the demand exceeds the alternator's supply.
- π¦ When the engine is off, the alternator stops charging, and the battery provides power to the car's electrical systems until it is depleted.
- π The battery consists of six separate chambers or cells, each generating around 2.1 volts of direct current (DC), for a total voltage of approximately 12.6 volts when connected in series.
- π Each cell contains lead plates submerged in an acid, creating a chemical reaction that releases energy. The size of the plates determines the current capacity, while the materials and number of plates determine the voltage.
- π« To prevent short-circuiting, the positive and negative plates are separated by an envelope separator, which is a porous material allowing ion flow without direct contact.
- π¬ The chemical reaction in the battery involves the interaction of lead oxide with sulfate from the electrolyte, forming lead sulfate layers on the electrodes and releasing electrons in the process.
- π§ The battery can be tested for voltage using a multimeter, with a reading of around 12.6 volts indicating proper function. A drop below 12 volts suggests the battery is not functioning correctly.
- π The alternator generates a higher voltage (around 14 volts) when the engine is running to recharge the battery and force electrons back into the chemical reaction.
Q & A
What is the primary function of a 12-volt lead acid car battery?
-The primary function of a 12-volt lead acid car battery is to provide the electrical energy needed to start the vehicle's combustion engine and to supply power to the vehicle's electrical systems when the engine is not running.
How does a lead acid battery store energy?
-A lead acid battery stores energy in the form of chemical energy. This chemical energy is converted into electrical energy when needed through a chemical reaction that releases energy, providing voltage and current.
What is the role of the starter motor in starting the engine?
-The starter motor engages a small gear onto the engine's flywheel, turning it to rotate the crankshaft, which starts the combustion engine. Once the engine starts, the starter motor disengages, and the engine runs by itself.
How does an alternator recharge the car battery?
-The alternator is connected to the engine and is rotated by it. As the alternator rotates, it generates electricity, which is fed back into the battery to recharge it while the engine is running.
What happens if the demand for electricity in the car exceeds the alternator's capacity?
-If the demand for electricity in the car exceeds what the alternator can provide, the battery steps in to provide the additional power, which can drain the battery.
What are the main components of a car battery?
-The main components of a car battery include a plastic case, a plastic lid with two terminals (positive and negative), six separate chambers or cells, plate straps, and grids coated in a paste of lead oxide.
How is the voltage of each cell in a car battery determined?
-Each cell in a car battery generates around 2.1 volts of direct current (DC). The cells are connected in series, and the voltages add up to provide a total voltage of around 12.6 volts.
What is the purpose of the separator between the positive and negative plates in a battery cell?
-The separator is a porous material that prevents the positive and negative plates from coming into direct contact, which would short-circuit the battery. It allows ions to flow through while keeping the materials separate.
How does the chemical reaction in a lead acid battery release electrons?
-The chemical reaction in a lead acid battery occurs between the lead oxide of the cathode and the sulfate in the electrolyte, forming lead sulfate and releasing oxygen ions. Simultaneously, lead atoms on the anode react with sulfate ions, creating a layer of lead sulfate and releasing electrons.
What is the difference between direct current (DC) and alternating current (AC)?
-Direct current (DC) is a type of electricity where electrons flow in one direction, like water flowing down a river. Alternating current (AC) is where electrons are pushed and pulled, flowing back and forth, similar to the tide of the sea.
How can the chemical reaction in a lead acid battery be reversed to recharge the battery?
-The chemical reaction can be reversed by supplying the battery with electricity from the alternator. This causes electrons to rejoin with the lead sulfate, releasing sulfate back into the electrolyte and strengthening the acid, while oxygen ions combine with lead to create lead oxide.
What could happen if a car battery is left to fully discharge for too long or too many times?
-If a car battery is left to fully discharge for too long or too many times, it becomes very difficult to reverse the chemical reaction. Additionally, the sulfate layer could break away from the electrodes and accumulate at the bottom of the battery, which means it will no longer participate in the chemical reaction, leading to the need for repair or replacement.
Outlines
π Understanding Car Batteries and Their Function
This paragraph introduces the 12-volt lead-acid car battery, a crucial component in combustion engine vehicles. It explains that these batteries store energy in chemical form and convert it into electrical energy when needed. The script also mentions the battery's rechargeable nature, its large current provision compared to household batteries, and its role in starting the engine by powering the starter motor. Additionally, it covers the battery's recharging process through the alternator and its function in supplying additional power when the car's electrical demand exceeds the alternator's capacity.
π The Internal Structure and Chemistry of Lead-Acid Batteries
The second paragraph delves into the internal structure of a lead-acid battery, highlighting its six separate cells, each generating about 2.1 volts of direct current when connected in series. It emphasizes the battery's construction with lead plates, plate straps, and the chemical paste that facilitates the reaction. The paragraph also discusses the importance of the separator that prevents short-circuiting and the electrolyte liquid composed of sulfuric acid and water. Furthermore, it touches on the fundamentals of electricity, including electron flow, conventional current theory, and the concept of ions and chemical reactions in batteries.
π The Electrochemical Process in a Battery Cell
This part of the script simplifies the complex construction of a battery into a single cell model to illustrate the electrochemical process. It describes the reaction between the lead oxide cathode and sulfate ions, forming lead sulfate and releasing oxygen ions, which then combine with hydrogen ions to form water. Simultaneously, the lead anode reacts with sulfate ions, releasing electrons and forming more lead sulfate. The buildup of electrons on the negative terminal creates a voltage difference, which can be measured and used to power devices. The paragraph also explains the process of recharging the battery and the importance of not allowing the battery to remain fully discharged for extended periods to prevent permanent damage.
π Squarespace Promotion and Continuing Education
The final paragraph shifts focus to a sponsored message encouraging viewers to use Squarespace to create an online presence for their projects. It highlights Squarespace's features, such as powerful blogging tools, appointment scheduling, and payment collection. The script provides a link for a free trial and a discount code for the first purchase of a website or domain. The video concludes with an invitation to follow the channel on various social media platforms and a teaser for the next lesson.
Mindmap
Keywords
π‘Lead Acid Car Battery
π‘Chemical Energy
π‘Starter Motor
π‘Alternator
π‘Direct Current (DC)
π‘Electrolyte
π‘Plate Straps
π‘Anode and Cathode
π‘Separator
π‘Rechargeable Battery
π‘Voltage
Highlights
12-volt lead acid car batteries are essential components in every combustion engine vehicle, providing the necessary electrical energy to start the engine and power the vehicle's electrical systems.
These batteries are rechargeable and store energy in the form of chemical energy, which is converted into electrical energy when needed.
The battery is composed of lead plates submerged in an acid, which creates a chemical reaction that releases energy to provide voltage and current.
Each cell within the battery generates around 2.1 volts of direct current (DC), and the cells are connected in series to achieve a total voltage of approximately 12.6 volts.
The starter motor uses the battery's electrical energy to start the engine by engaging a gear onto the engine's flywheel, which turns the crankshaft.
The alternator, connected to the engine, generates electricity to recharge the battery and power the vehicle's electrical systems when the engine is running.
When the vehicle's electrical demand exceeds the alternator's capacity, the battery provides additional power to meet the demand.
The battery's main parts include a plastic case, a plastic lid with two terminals, and six separate chambers, each functioning as a cell.
Each cell contains plate straps made from lead, which are connected to a number of plates coated in a paste of lead oxide where the chemical reaction occurs.
The battery's chemical reaction involves the interaction between the lead oxide in the positive plate (cathode) and the lead in the negative plate (anode) with the sulfuric acid electrolyte.
The battery's operation can be monitored by measuring the voltage across its terminals; a fully charged battery should read around 12.6 volts.
During the starting of the car, the voltage may drop due to the starter motor drawing a large current, but it should not fall below 10 volts for the battery to function properly.
When the engine is running, the alternator generates a higher voltage of around 14 volts to recharge the battery.
If the battery is left to fully discharge for too long or too many times, the chemical reaction becomes difficult to reverse, and the battery may need to be repaired or replaced.
The video provides a simplified model of a battery cell to explain the chemical reactions involved in converting chemical energy to electrical energy and vice versa.
Squarespace is mentioned as a platform for creating an online web presence, with features for blogging, scheduling appointments, and collecting payments.
The video concludes with an encouragement to continue learning and following the channel on various social media platforms for more educational content.
Transcripts
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