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can a 12v lawn mower sealed battery be charged with 12v battery charger use on cars
If it is totally dead charge it for 2 hours at 10 amps.
Depends on the amperage of the charger. A 10 amp charger will charge it in about 1 hour.
That depends on the amp-hour capacity of the battery.
No
Yes, you can charge a 12V 7.2Ah battery with a 12V 300mA charger, but it may take a long time to fully charge the battery due to the lower current output. The charger will provide a safe voltage for the battery, but the charging time could be significantly extended compared to a charger with a higher current output. Ensure the charger is compatible with the battery chemistry to avoid any damage.
Till the battery is fully charged. -Could be 4-12 hours.
A good auto battery will hold it's charge for at least 6 months or longer.
Yes, you can charge a 12V 12Ah battery with a 12V 7Ah charger, but it may not be optimal. The 7Ah charger will charge the 12Ah battery more slowly than a charger with a higher output. Additionally, if the battery is significantly discharged, charging with a lower capacity charger could take a long time and may not fully charge the battery if the charger cannot provide enough current. Always monitor the charging process to ensure safety.
No.
No
No, you need at least 12v to charge 12v. Most alternators charge at 13-14 volts.