···
Log in / Register

How many hours does it generally take to charge a car battery when it's dead?

4 Answers
StAmara
09/07/25 3:49am

When a car battery is dead, the charging time is generally 10-15 hours. Here is more information about car batteries: 1. Charging time: The charging time is 10-15 hours. If the charging time is insufficient, the battery won't be fully charged, which will directly affect the vehicle's driving performance. 2. Car battery maintenance: (1) Use a damp cloth to wipe the exterior of the battery, removing dust, oil stains, white powder, and other contaminants that may cause leakage from the panel and terminals (positive and negative poles). Regularly cleaning the battery terminals prevents the buildup of white acidic corrosion powder and extends the battery's lifespan. (2) Check if the battery is charging properly. If you have a multimeter, measure the voltage across the battery terminals after starting the engine. It should exceed 13V to be considered normal. If the charging voltage is too low, you should have a professional inspect the charging system.

Was this review help?
17
0
Share
StPreston
09/19/25 3:16am

I've had several experiences with a dead battery, and the charging time mainly depends on the battery capacity and charger power. A regular car battery typically has a capacity between 50 to 70 ampere-hours. If you use a 5A charger, it usually takes about 10 to 14 hours to fully charge. However, don't rush to use the high-current mode—while it can provide a quick start, it will shorten the battery's lifespan. I recommend using the slow-charging mode and letting it charge overnight in a well-ventilated area, such as from evening until early morning, which works well. Before charging, remember to check the battery voltage—if it's below 11 volts, it might indicate aging or a short-circuit issue. Using a smart charger is more convenient, as it can automatically detect and prevent overcharging. Additionally, in winter's low temperatures, battery performance drops, and charging time may extend by one to two hours, so extra attention is needed. Regular maintenance is key, and avoid long-term parking to prevent battery drain.

Was this review help?
10
3
Share
Expand All
StTravis
11/02/25 3:37am

As someone who frequently drives, let me share some practical tips. The charging time for a dead battery typically ranges from 6 to 12 hours. With a standard 10A charger, a medium-sized battery can usually start the car after about five hours of charging, but for battery health, it's best to let it fully charge—I usually set it for 10 hours. Before charging, make sure the engine is off and all electrical devices are disconnected to avoid accidents. Choose an open outdoor area for charging to minimize risks. If the battery has been left unused for too long and the voltage is too low, it might not charge properly, requiring a replacement or professional assistance. It's advisable to keep a portable charger on hand for emergencies. Regularly checking the voltage is a good habit to detect issues early.

Was this review help?
6
3
Share
Expand All
LaBrianna
12/16/25 3:41am

Hey, my car battery died last month, so I bought a portable charger for emergencies. It usually takes three to four hours to start the car, but my friend suggested charging for more than eight hours to fully revive the battery. Depending on the charger's power and the battery size, it generally takes six to ten hours. Remember not to lock the car doors while charging to avoid any issues. If the battery is in good condition, it should work smoothly after charging.

Was this review help?
14
0
Share
Expand All
More Forum Discussions

What is the difference between 0w40 and 5w40?

The differences between 0w40 and 5w40 are: 1. Different references: 0w40 refers to fully synthetic oil; 5w40 refers to semi-synthetic oil. 2. Different definitions: 0w40 is a man-made engine oil that undergoes chemical decomposition of various natural substances during production; 5w40 is one type of automotive engine oil, where semi-synthetic oil uses semi-synthetic base oil. Engine oil, also known as motor lubricant, serves to lubricate and reduce friction in the engine, assist in cooling, seal against leaks, prevent rust and corrosion, and act as a shock absorber. Engine oil consists of two parts: base oil and additives. The base oil is the main component of lubricating oil, determining its fundamental properties, while additives compensate for and improve the shortcomings of the base oil, imparting certain new characteristics.
11
3
Share

Why Does an Automatic Transmission Car Stall?

The reasons for an automatic transmission car stalling are: 1. Low-voltage power failure or quenching during driving causing circuit malfunctions; 2. Faulty equipment such as ignition coils, capacitors, or electronic ignition modules; 3. Fuel system failures, damaged air pumps, ruptured pipes, clogged carburetor inlets, or an empty fuel tank. The steps to restart an automatic transmission car after stalling are: 1. Shift the gear to P or N position; 2. Turn the key to the ON position and check if all indicators on the dashboard display normally; 3. Start the engine after the self-check is completed; 4. Drive at idle speed until the RPM drops below 1000, then drive normally after the water temperature rises.
19
3
Share

What is the difference between a 1.5t engine and a 2.0t engine?

1.5t engine and 2.0t engine differences are: 1. Different displacement: The displacement of the 1.5t engine is 1.5L; The displacement of the 2.0t engine is 2.0L. 2. Different road condition adaptability: The 1.5t engine is suitable for daily urban driving; The 2.0t engine is suitable for high-speed driving. 1.5 and 2.0 represent the engine displacement, and t represents turbocharging. An engine is a machine that can convert other forms of energy into mechanical energy, including: 1. Internal combustion engine; 2. External combustion engine; 3. Gas turbine; 4. Jet engine.
9
2
Share

How to Automatically Adjust the Rearview Mirror When Reversing in a Mercedes-Benz GLA?

Mercedes-Benz GLA's method for automatically adjusting the rearview mirror when reversing is: 1. Place the left and right rearview mirror switch in the middle; 2. Press the downward adjustment button in all four directions. The Mercedes-Benz GLA is a compact SUV under Beijing Benz. Taking the Mercedes-Benz GLA 2020 180 as an example, its body dimensions are: length 4427 mm, width 1834 mm, height 1610 mm, with a wheelbase of 2729 mm. The Mercedes-Benz GLA 2020 180 is equipped with a 1.3T inline 4-cylinder turbocharged engine, with a maximum power of 110 kW, maximum power speed of 5500 rpm, maximum torque of 250 Nm, and maximum torque speed ranging from 1460 to 4000 rpm.
14
1
Share

What is the classification standard for sedan levels?

The classification standard for sedan levels is divided into four categories: A, B, C, and D. Class A cars, also known as compact cars: There are even smaller cars referred to as subcompact cars, or A0-class cars, such as the Vios, Fit, and Polo. Some current compact cars have begun to be lengthened, such as the Lavida, Lamando, and Corolla, which some media refer to as A+ class cars. Their wheelbase is approximately 2.4 to 2.6 meters, and their displacement mostly ranges from 1.0 to 1.5 liters. Class B cars, also known as midsize cars: Models like the Magotan, Passat, Camry, Accord, BMW 3 Series, and Audi A4 belong to this category. Their wheelbase is around 2.7 to 2.9 meters, and their displacement ranges from 1.4 to 2.5 liters. Class C cars, also known as full-size cars: Their wheelbase is about 3 meters, and their displacement ranges from 2.0 to 3.0 liters. The most common Class C cars are the Audi A6, BMW 5 Series, and Mercedes-Benz E-Class. These cars can be considered luxury vehicles and are often used by large enterprises for business reception purposes. Class D cars, also known as large luxury cars: These are luxury cars that can be described as perfect. Their wheelbase varies from 3.1 to 3.6 meters, and their displacement ranges from 2.0 to 6.6 liters. Representative models include the Mercedes-Benz S-Class, BMW 7 Series, Audi A8, Lexus LS, Bentley, and Rolls-Royce, among others.
12
4
Share

What Causes a Strong Gasoline Smell When Turning on the Car Heater?

Strong gasoline smell when turning on the car heater can be caused by: 1. Damaged carbon canister; 2. Overfilled fuel tank; 3. Damaged fuel pipe joints, injector seals, or carbon canister solenoid valve. Solutions for strong gasoline smell when using the car heater include: 1. Replacing the gasket inside the fuel tank cap; 2. Replacing the gasoline rubber hose; 3. Cleaning components such as the fuel pump, fuel filter, carbon canister, fuel injectors, and throttle body. The car heater utilizes waste heat generated by the engine operation. When the engine's cooling system dissipates heat from the engine, a fan directs this heat into the cabin to provide warm air. When the heater is not in use, the fan stops, the heating vents close, and the dissipated heat is released into the air. The car heater is essentially a form of waste heat recycling.
6
3
Share
Cookie
Cookie Settings
© 2025 Servanan International Pte. Ltd.