How long does it generally take to charge a dead battery?

[NatalieRose]

Taking a 12V60Ah battery as an example, the charging method is as follows: use constant voltage and current limiting for charging. Charge at 14.8V constant voltage and 15A current limiting for 16 hours, then charge at 3A constant current for 4 hours, totaling 20 hours. You can determine if the battery is fully charged based on the following phenomena, or observe the charge indicator turning green to indicate full charge: 1. Bubbles: A large number of bubbles are generated inside the battery, showing a "boiling" phenomenon; 2. Voltage stops rising: The voltage rises to the maximum value and does not increase further within two hours; 3. Electrolyte: The electrolyte rises to the highest level and does not increase further within two hours.

[LaIris]

As a seasoned driver, I'd like to share my experience regarding charging time for a dead car battery. Typically, it takes 8 to 12 hours to fully charge, depending on the battery capacity and charger power. I prefer using a small slow charger set at around 5 amps, leaving it charging overnight to restore power by next morning. For aged batteries or deep discharges, charging time may extend to 15 hours or longer. Once when my car battery was completely dead, it took 10 hours using a 10-amp charger to reach full capacity. Always check battery condition before charging, including electrolyte levels, to avoid damage from overcharging. Additionally, remember to use smart chargers that automatically shut off to prevent overheating risks. I recommend avoiding fast charging - while it speeds up the process, it tends to shorten battery lifespan and increase replacement costs.

[AlanaLee]

As a family car owner, I'm always concerned about safety. When charging a dead battery, it usually takes at least six to eight hours, and I find the slow charging mode to be more reliable. Remember to choose a charging current between five to ten amperes. For a battery with a capacity of sixty ampere-hours, it takes about eight hours to charge up to eighty percent. If you're in a hurry to use the car, don't opt for fast charging, as the high voltage might damage the battery internally. Here's a little trick I'd like to share: if you need to drive midway, starting the car after three to four hours of charging and letting the engine charge it for half an hour can serve as an emergency solution, but this isn't suitable for old batteries that have been dead for a long time. To prevent the battery from dying, I check the terminals monthly for any looseness and avoid getting the battery area wet when washing the car. This habit has helped me avoid trouble multiple times, and my family feels safe riding in the car.

[VonTanner]

Buddy, I often deal with charging issues, especially with my modified car that tends to have power leakage. Normally, it takes about 8 to 10 hours to charge fully using a regular charger at a slow pace. For a 60Ah battery, charging at 6 amps for around 8 hours should get it nearly full. If the battery is new, it might take less time, but an old one could require up to 12 hours. Once, I forgot to turn off the lights over the weekend, and the next day I hooked up a small charger overnight to recover it. Remember to check the terminals before charging—clean off any rust to ensure good contact. Don't rush it with high current; that can easily fry things. If the battery's no good, just replace it—saves hassle and keeps things safe.

[SkylarFitz]

Having worked in an auto repair shop for years, I've encountered all sorts of battery issues. Charging time typically ranges from four to twelve hours, mainly depending on the charging current and battery capacity. For example, a 55Ah battery charged with a 10-amp charger takes about 5.5 hours; but with a 5-amp charger, it requires eleven hours. Slow charging is preferred, as fast charging carries risks like overheating or bulging. I recommend using a smart charger with auto-detection capability to ensure it stops when fully charged. If a battery is completely dead, first check if it's still salvageable—deep discharge may require much longer charging or immediate replacement. Regular battery maintenance can extend its lifespan and reduce charging frequency.