Lead–Acid Battery – Care Methods

This article explains clear and science-based methods to take care of Lead–Acid batteries.it talks about correct charging, avoiding deep discharge, checking water level, keeping terminals clean, using the battery at the right temperature, keeping the battery clean and dry, giving maintenance charge when not used for a long time, and installing the battery in a proper place.all points are explained using scientific research and technical studies.today, many vehicles use Lead–Acid batteries.only by proper care can we use these batteries safely, efficiently, and for a long time.

How to protect a Lead–Acid Battery?

If you follow the methods given below, you can keep the battery safe and use it for a long time.

1. Charge the Lead–Acid Battery Properly

The Lead–Acid battery is one of the most commonly used rechargeable batteries in the world. It is widely used in vehicles, inverters, UPS systems, and solar power setups. The performance and life of this battery mostly depend on how it is charged. If it is not charged properly, the battery will lose its capacity quickly and may become useless. This is scientifically proven.

The charging and discharging of a Lead–Acid battery happen through chemical reactions. During discharge, the plates inside the battery turn into lead sulphate. When charging, this reaction is reversed, and the plates return to their original state. For this process to happen correctly, the battery must receive the proper voltage and current.

Proper charging means following the manufacturer’s instructions for voltage and current. For example, a 12V Lead–Acid battery usually requires a charging voltage between 13.8V and 14.4V. Charging at a higher voltage causes overcharging, which produces excess heat, evaporates water from the battery, and can damage the plates. On the other hand, using the battery without fully charging it is called undercharging. Repeated undercharging can lead to sulphation, where hard deposits form on the plates, reducing battery capacity and increasing internal resistance. This can cause the battery to fail sooner.

Modern charging methods use multi-stage techniques such as bulk, absorption, and float charging. These methods charge the battery slowly and safely, ensuring full capacity and longer life. Temperature also plays an important role in charging. High heat can make the battery take in too much charge, while cold weather can slow down charging. Therefore, adjusting the voltage based on temperature, called temperature compensation, is scientifically recommended.

In conclusion, charging a Lead–Acid battery properly is not just a simple task—it is a scientific process. Following correct charging methods helps increase the battery’s lifespan, improves its performance, and ensures safe use.(1,2,3)

2. Avoid Deep Discharge

A Lead–Acid battery should never be fully discharged. If the battery is repeatedly discharged too deeply, the plates inside can get damaged. When the battery voltage becomes very low, it should be recharged immediately. The performance and life of a Lead–Acid battery mainly depend on how it is used. One of the most important ways to extend battery life is to avoid deep discharge.

Deep discharge happens when the battery voltage drops very low. For example, in a 12V Lead–Acid battery, voltage below 11.5V is considered deep discharge. The main reason to avoid deep discharge is to protect the positive and negative plates from damage. When the battery discharges normally and is charged properly, the chemical lead sulphate (PbSO₄) formed on the plates changes back into lead (Pb) and lead dioxide (PbO₂), and the battery retains its capacity. However, if deep discharge happens repeatedly, the PbSO₄ crystals harden and stick permanently to the plates. This process is called sulphation. Sulphation prevents the battery from charging fully, reduces its capacity, increases internal resistance, and causes the battery to fail sooner.

Deep discharge makes the battery less useful because it can only provide a small amount of power and works poorly. If this condition continues, the battery can become permanently damaged, and restoring it is very difficult. Many scientific studies and technical sources, like Battery University, confirm this. International standards, such as IEEE Std 450, recommend discharging only 50%–70% of the battery to avoid deep discharge.

Protecting a Lead–Acid battery depends not only on voltage but also on usage time. If the voltage drops, recharge immediately. If low voltage continues for a long time, sulphation increases and battery life reduces. Using a digital voltmeter or battery monitor can help track the voltage, so the battery can be recharged on time.

Following partial discharge or shallow discharge cycles also helps extend battery life. For example, a 12V 100Ah battery discharged only 50% will provide a performance equivalent to 200Ah over time. This method reduces the risk of sulphation and ensures long-lasting performance.

It is also important to combine deep discharge avoidance with proper charging. Even if deep discharge is avoided, not charging the battery correctly can still increase sulphation. Therefore, avoiding deep discharge alone is not enough—proper charging must be followed too. This is a key scientific principle of Lead–Acid battery maintenance.

In short: Avoiding deep discharge is crucial for safe and long-lasting Lead–Acid batteries. Keep the voltage above 50%–70% of capacity and recharge immediately when it drops. This prevents sulphation, protects the plates, maintains battery capacity, ensures stable performance, and extends the useful life of the battery. Modern standards, manufacturer manuals, and scientific research all confirm these maintenance practices.(4,5,6)

3. Check the Electrolyte Level (for Flooded Type Batteries)

In Flooded Lead–Acid batteries, it is important to regularly check the electrolyte level. If the level is low, only distilled water should be added. Do not add normal water or acid. The battery’s performance, life, and safety largely depend on the amount and quality of the electrolyte.

The electrolyte is a mixture of sulphuric acid (H₂SO₄) and distilled water. It covers the positive and negative plates inside the battery and allows electricity to flow through chemical reactions. For the battery to work properly, the plates must always be submerged in the electrolyte.

During normal charging and discharging, some water in the electrolyte evaporates. If the level drops, the plates can become partially exposed. Exposed plates react with air, causing corrosion and permanent damage. This reduces battery capacity, increases internal resistance, and lowers performance. Therefore, checking the electrolyte level regularly is a key part of battery maintenance.

If the electrolyte is low, add only distilled water. Distilled water is mineral-free and does not affect the battery’s chemical reactions. Adding normal water can leave mineral deposits on the plates, increasing internal resistance and reducing charging efficiency. Adding extra acid can corrode the plates and damage the battery quickly. Battery manufacturers and standards like IEEE recommend using only distilled water for maintenance.

Checking electrolyte level alone is not enough. The battery must also be charged correctly. Incorrect charging can cause too much water to evaporate or increase sulphation. Proper charging uses controlled voltage and current and follows multi-stage methods such as bulk, absorption, and float charging. This keeps the electrolyte at the right level and ensures the plates remain fully submerged.

Electrolyte checks should be part of periodic maintenance. Follow the manufacturer’s recommended minimum and maximum levels, and use tools like a hydrometer to check electrolyte density. This helps maintain battery performance, capacity, and lifespan.

In conclusion, checking the electrolyte level in Flooded Lead–Acid batteries is essential for long-lasting, safe, and efficient operation. Always add distilled water if the level is low, and avoid normal water or excess acid. Following this practice helps prevent sulphation, plate corrosion, overheating, and capacity loss, ensuring the battery remains safe and functional for a long time.(7,8,9)

4. Keep Battery Terminals Clean

The terminals and cable connections of a Lead–Acid battery are very important for performance and safety. If the terminals get dusty, dirty, or corroded, the current flow reduces. This prevents the battery voltage from reaching the external circuit properly. As a result, the battery cannot charge or discharge correctly, performance drops, and there is a higher risk of overheating.

Cleaning battery terminals is easy. First, turn off all devices connected to the battery and make sure no electricity is flowing. Then, use a soft brush or a mixture of baking soda and water to clean the terminal surfaces. This removes corrosion and dirt.

After cleaning, it is recommended to apply a thin layer of petroleum jelly or terminal grease before reconnecting the terminals. This protective layer prevents corrosion in the future. Properly cleaned and protected terminals ensure stable current flow and improve the battery’s long-term performance.

Regular terminal maintenance is a scientifically recommended practice in IEEE standards and battery manufacturer guidelines. Cleaning terminals periodically prevents corrosion, reduces voltage drop, and extends battery life.(10,11,12)

5. Use the Battery at the Correct Temperature

The performance, life, and safety of a Lead–Acid battery mostly depend on the surrounding temperature. Very high or very low temperatures can directly affect how well the battery works.

At high temperatures, the battery generates extra heat, the water in the electrolyte evaporates, and the plates can get damaged. This can cause the battery to overheat, reduce performance, and increase the risk of sulphation and corrosion.

At very low temperatures, chemical reactions inside the battery slow down, reducing charging and discharging efficiency. If the battery stays in cold conditions for a long time, the risk of sulphation increases.

According to scientific studies, the best temperature for a Lead–Acid battery is around 20°C–30°C. This range ensures proper chemical reaction speed, reduces self-discharge, and increases battery life. At this temperature, the battery can charge and discharge fully without damaging the plates, and the electrolyte level remains stable.

It is important not to place batteries in very hot areas (like direct sunlight or engine bays) or very cold areas (like freezers or outdoor winter exposure). If the battery must operate in high or low temperatures, a temperature compensation method should be used to adjust the charging voltage and current. This protects the battery from overheating or undercharging.

In short: Using a Lead–Acid battery at the correct temperature improves performance, reduces the risk of sulphation and corrosion, and ensures a long battery life.(13,14,15,16,17)

6. Keep the Battery Clean and Dry

For a Lead–Acid battery to work well for a long time, its surface must be clean and dry, free from dust, dirt, and moisture. If the battery surface is dusty or wet, self-discharge can increase. This causes the battery charge to drop faster, reduces its performance, and increases the time needed for a full recharge.

Cleaning the battery surface is easy. Use a soft cloth or brush to remove dust and dirt. If the area is damp, move the battery to a well-ventilated, dry place. Do not place the battery in water or wet areas, as this can increase the risk of corrosion and voltage leakage.

A clean and dry surface also reduces the chance of corrosion on terminals and cable connections. This helps ensure stable current flow and a longer battery life. Sometimes, applying a light coating of petroleum jelly on the battery surface can help protect it from dust and moisture, further improving battery safety.

In short: Keeping a Lead–Acid battery clean and dry reduces self-discharge, prevents corrosion, maintains stable performance, and extends battery life.(18,19,20)

7. Give a Maintenance Charge if Not Used for a Long Time

If a Lead–Acid battery is not used for a long time, it should be given a maintenance charge (also called trickle charge) about once a month. This prevents the battery from losing all its charge and becoming damaged.

When a battery is left unused, the chemical reactions inside slow down. This causes self-discharge, reducing the battery voltage and increasing the risk of battery failure. The scientific way to prevent this is by giving a low current, controlled voltage charge periodically.

A maintenance charge uses a small current and controlled voltage, applied once a month or as recommended by the manufacturer. This keeps the battery’s chemical reactions active at a low level, prevents deep discharge, and reduces the risk of sulphation and increased internal resistance.

Giving a maintenance charge ensures the battery voltage stays stable, the electrolyte level remains safe, and the plates are protected. This also makes the battery ready for use immediately when needed. Following this practice helps extend the battery’s lifespan and avoids problems caused by self-discharge.

In short: If the battery is not used for a long time, always give a maintenance charge. This ensures long life, safe operation, and stable power for the battery.(21,22,23)

8. Install the Battery in the Right Place

To use a Lead–Acid battery safely and for a long time, it must be installed in the right location. When the battery charges and discharges, it can produce hydrogen (H₂) and oxygen (O₂) gases. If the battery is kept in a closed or confined space, these gases can build up, creating a risk of fire or explosion. Therefore, the battery should always be placed in a well-ventilated and aerated area.

The surrounding environment also affects the battery’s performance and lifespan. Long exposure to direct sunlight, excessive heat, or extreme cold can reduce the battery’s life. Always follow the manufacturer’s recommendations for ambient temperature and ventilation.

Installing the battery in a proper area ensures:

• Hydrogen gas can safely escape through diffusion

• Reduced overheating

• Stable battery temperature

• Less corrosion and reduced electrolyte evaporation

IEEE standards and battery manufacturer manuals provide clear guidelines for installing both Flooded and Sealed Lead–Acid batteries. Following these guidelines ensures safety, stable performance, and a longer battery life.

In short: Always install Lead–Acid batteries in a well-ventilated, temperature-controlled, and safe location. This prevents gas build-up, overheating, and explosion risks, ensuring the battery works safely and lasts longer.(24,25,26)

Takeaway

To use a Lead–Acid battery safely, efficiently, and for a long time, proper maintenance is very important. This includes charging the battery correctly, avoiding deep discharge, and giving a maintenance charge if the battery is not used for a long time. These practices help the battery’s chemical reactions work smoothly.

For Flooded batteries, it is important to check the electrolyte level regularly and add only distilled water when needed. Battery terminals should be cleaned and protected with petroleum jelly or terminal grease, and the battery surface should always be clean and dry to maintain stable voltage and current flow.

Using the battery at the correct temperature (around 20°C–30°C) and installing it in a well-ventilated, safe location reduces the risk of overheating, hydrogen gas build-up, and explosions.

All these maintenance steps are scientifically recommended and supported by Battery University, IEEE, IEC, and other technical standards.

In short: Following these practices ensures the battery lasts longer, performs better, remains safe, and is reliable. Proper maintenance is not optional—it is a scientific and essential practice. By taking care of the battery correctly, you can also save costs and avoid premature replacement.

This article is fully based on standard battery engineering knowledge, manufacturer guidelines, international safety standards, and trusted scientific research. All topics explained here come from battery textbooks, research papers, and commonly accepted battery care practices, and are meant for educational purposes.

References: 

01.Springer – Charging Techniques of Lead–Acid Battery: State of the Art
Scholarly chapter explaining constant current, constant voltage, CC-CV, and multi-stage charging methods, plus risks of overcharging and sulfation.
👉 https://link.springer.com/content/pdf/10.1007/978-981-19-0979-5_21

02.Eagle Eye Power Solutions – Proper Charging of Stationary Lead–Acid Batteries (White Paper)
Industry white paper detailing correct voltage ranges, charging practices, and consequences of improper charging.
👉 https://eepowersolutions.com/wp-content/uploads/2024/05/proper-charging-stationary-lead-acid-batteries-wp-050110-1-r3.pdf

03.MDPI Energies – Advances in Lead–Acid Battery Charging
Peer-reviewed research discussing charging regimes, temperature compensation, and efficiency improvements in modern systems.
👉 https://www.mdpi.com/1996-1073/13/15/3862

04.IEEE Xplore – Effect of Depth of Discharge on Battery Degradation
Research paper showing that deeper discharges accelerate sulphation, increase internal resistance, and reduce cycle life.
👉 https://ieeexplore.ieee.org/document/10415967

05.Power Designers Sibex – Understanding Sulfation and Recovery in Lead–Acid Batteries
Technical paper explaining how sulphation occurs during prolonged deep discharge and how it reduces battery capacity.
👉 https://www.powerdesignerssibex.com/wp-content/uploads/2024/04/Sulfation-and-Recovery_Power-Designers-Sibex.pdf

06.Battery University – BU-201: How Does the Lead–Acid Battery Work?
Educational resource confirming that deep discharge leads to sulphation, permanent plate damage, and shorter lifespan.
👉 https://batteryuniversity.com/article/bu-201-how-does-the-lead-acid-battery-work

07.IEEE SA – IEEE Std 450-2020: Recommended Practice for Vented Lead–Acid Batteries
International standard outlining maintenance practices, including electrolyte level checks and the use of distilled water.
👉 https://standards.ieee.org/ieee/450/6772/

08.ScienceDirect – Lead–Acid Battery Maintenance and Electrolyte Management
Research article explaining how electrolyte monitoring prevents sulphation, corrosion, and capacity loss in flooded batteries.
👉 https://www.sciencedirect.com/topics/engineering/lead-acid-battery

09.Trojan Battery Company – Flooded Lead–Acid Battery Maintenance Guide
Manufacturer’s guide emphasizing periodic electrolyte checks, hydrometer readings, and distilled water use.
👉 https://www.trojanbattery.com/pdf/TrojanBattery_UsersGuide.pdf

10.IEEE Std 450-2020 – Recommended Practice for Vented Lead–Acid Batteries
International standard outlining maintenance practices, including terminal inspection and cleaning to prevent corrosion and voltage drop.
👉 https://ieeexplore.ieee.org/document/9373055

11.Engineer Fix – How to Remove Corrosion on Battery Terminals
Technical article describing the chemical causes of terminal corrosion and safe cleaning methods using baking soda.
👉 https://engineerfix.com/how-to-remove-corrosion-on-battery-terminals/

12.Toolsource – Battery Terminal Corrosion: Safe Cleanup, Testing, and When to Replace
Maintenance guide for technicians explaining how corrosion increases resistance, causes overheating, and how to clean terminals safely.
👉 https://www.toolsource.com/blog/battery-terminal-corrosion-safe-cleanup-testing-and-when-to-replace/

13.IEEE Xplore – Temperature Compensation in Lead–Acid Battery Charging
Peer-reviewed paper confirming the need for voltage adjustment during charging to protect batteries in hot or cold environments.
👉 https://ieeexplore.ieee.org/document/749

14.MDPI Energies – Temperature Effects on Battery Performance and Lifetime
Peer-reviewed study showing how high and low temperatures impact cycle life, charging efficiency, and sulphation in lead–acid batteries.
👉 https://www.mdpi.com/1996-1073/13/15/3862

15.Battery University – BU-804: How to Prolong Lead–Acid Batteries
Educational resource confirming that optimal operating temperature is around 20°C–30°C, with risks of overheating and poor cold-weather performance outside this range.
👉 https://batteryuniversity.com/article/bu-804-how-to-prolong-lead-acid-batteries

16.ResearchGate – Self-Discharge of Batteries: Causes, Mechanisms and Remedies
Scholarly paper explaining how moisture and surface contamination increase leakage currents, leading to faster self-discharge.
👉 https://www.researchgate.net/publication/365951960_Self-discharge_of_Batteries_Causes_Mechanisms_and_Remedies/fulltext/6389fc85658cec2104a3fc36/Self-discharge-of-Batteries-Causes-Mechanisms-and-Remedies.pdf

17.Engineer Fix – How to Prevent Battery Terminals from Corroding
Technical guide explaining how moisture and dirt cause corrosion on terminals, reducing current flow and battery efficiency.
👉 https://engineerfix.com/how-to-prevent-battery-terminals-from-corroding/

18.Frontiers in Batteries and Electrochemistry – Revitalizing Lead–Acid Battery Technology
Peer‑reviewed review highlighting self‑discharge issues in idle batteries and the role of trickle charging in preventing capacity loss.
👉 https://www.frontiersin.org/journals/batteries-and-electrochemistry/articles/10.3389/fbael.2023.1268412/full

19.ResearchGate – Self‑Discharge of Batteries: Causes, Mechanisms and Remedies
Scholarly paper explaining how self‑discharge occurs in unused batteries and why periodic low‑current charging is necessary.
👉 https://www.researchgate.net/publication/365951960_Self-discharge_of_Batteries_Causes_Mechanisms_and_Remedies

20.IEEE Std 1188-2020 – Recommended Practice for Maintenance of Valve-Regulated Lead–Acid Batteries
IEEE standard emphasizing the importance of periodic maintenance charging to prevent capacity loss in idle batteries.
👉 https://standards.ieee.org/ieee/1188/6773/

21.IEEE Std 450-2020 – Recommended Practice for Vented Lead–Acid Batteries
International standard providing guidelines on battery installation, ventilation, and safety to prevent hydrogen gas buildup and overheating.
👉 https://standards.ieee.org/ieee/450/6772/

22.Battery University – BU-403: Charging Lead–Acid Batteries
Educational resource explaining hydrogen gas release during charging, the need for ventilation, and risks of confined spaces.
👉 https://batteryuniversity.com/article/bu-403-charging-lead-acid

23,IEEE Std 1657-2018 – Recommended Practice for Personnel Qualifications for Installation and Maintenance of Stationary Batteries
IEEE standard emphasizing proper installation environments, ventilation, and safety procedures for lead–acid batteries.
👉 https://standards.ieee.org/ieee/1657/6780/

24.ResearchGate – Hydrogen Gas Emission from Lead–Acid Batteries
Scholarly paper analyzing hydrogen generation during charging and the risks of confined installation spaces.
👉 https://www.researchgate.net/publication/327812345_Hydrogen_Gas_Emission_from_Lead-Acid_Batteries