the ideal current or amps to charge a car battery are 20% of its full capacity e.g 10 amps for a 50Ah battery the ideal charging current for a 12v 7ah battery is 1.4 amps maximum charging current for 100Ah battery should not be above its 20% of full capacity (20 amps)
Generally, the charging current for a 12V battery is around 10% of the battery’s capacity. Charging current can vary based on battery type; lead-acid batteries are generally charged at a rate of 10% of their capacity, while lithium-ion batteries can handle higher charging currents, sometimes up to 100% of their capacity.
The primary use of a car battery is to start the engine, and for this, it needs a lot of power. For this reason, you should keep your car battery at or close to 100% charge. If your lead-acid battery is left in a partial charge state, below 12.5 volts, there is the potential for damage.
Car battery voltage typically ranges from 12.6 to 14.4 volts, with the alternator charging the battery while the engine runs. Monitoring battery voltage using the chart ensures optimal performance and prevents unexpected breakdowns. This chart helps in assessing the battery’s state and ensuring proper performance.
Most modern car battery chargers will charge a car battery only up to about 70% of its capacity. This phase can take an additional 5 to 7 hours and uses a reduced current to charge the battery up to its full capacity.
This is why a battery charger can operate at 14-15 volts during the bulk-charge phase of the charge cycle When your battery is below 80% charged it will safely accept the higher voltage (read the spec of your battery to figure out the maximum voltage) and maximum current (Which should not be 20% of the total capacity of your battery)