Yes. Apply a 24 volt charger to it. A charger is used to apply a voltage slightly higher than the rated voltage for any battery under charge. If the voltage of the charger is mismatched to the battery under charge, you may overcharge the battery.
How to calculate charging time yourself?
- Divide the load power by 1,000 for a value in kilowatts.
- Divide the power of your battery (also in kW) by the figure obtained to get the charging time.
- First calculate your load power (P), by multiplying the voltage (U in volts) by the current (I, in amps).
Manufacturers recommend recharging when the battery reaches about 70% of its capacity (approximately 2.1 volts per cell). Taper Current Charging: this method is not really recommended for charging SLA batteries as it can often shorten battery service life due to poor control of the final fully charged voltage.
"Maintenance Free" just means that you don't have to top it up with distilled water regularly. It's fine to charge it up - but I recommend you take it to a car spares store - they can test whether it's worth charging, or if the battery has just reached the end of it's life.
A 12-volt automotive battery, for instance, takes a while to charge. In fact, fast charging for this kind of battery is not recommended. 10 amps are the recommended current. This is a slow charge.
When overcharged, lithium ion batteries may overheat, explode and cause fires. Even slight overcharging reduces a cell's discharge capacity, leading to overdischarging, which increases impedance and heat generation, and decreases cell lifetime.
So most probably YES you can charge using this charger if and only if you limit the charging current to the battery. You will need to adapt & check a few steps: Limit inrush current to I< 0.39A.
The average time it takes to charge a sealed lead acid rechargeable battery is anywhere from 12 – 16 hours and up to 48 hours for large stationary batteries. Sealed Lead Acid batteries are not very quickly replenished and do not recharge as fast as other battery systems.
For example, to fully recharge a 12 Volt 7 Amp Hour (12V 7Ah) SLA battery using a 12V 1.8Ah charger would take approximately 4.5 hours if the battery is fully discharged.
Overcharging a lead acid battery can be just as harmful as undercharging it. If workers leave the battery in a continuously charging state for long periods of time, corrosion of the positive battery plates can occur. Lead acid batteries can also get very hot while charging.
Attach a battery trickle charger or a computerized smart charger to your old lead acid battery, and allow charging continuously for about a week to 10 days. The extremely slow charging rates dissolve the de-sulphation that kills the battery, and revives it back to being able to hold a usable charge.
How to Test Sealed Lead Acid Batteries
- Test the battery voltage. Set the voltmeter dial to DC (direct current) volts. Place the voltmeter leads on the positive and negative battery posts.
- Charge the battery. Perform a high-rate charge test.
- Perform a slow charge test. Slow charge the battery for several hours.
Those batteries that are used in deep discharge cycling mode can be charged up to 2.45 volts/cell (14.7V for a 12V battery) to get the highest charge rate, as long as the voltage is dropped to the float voltage when the charge is complete.
Slow charging rates vary depending on the battery's type and capacity. However, when charging an automotive battery, 10 amps or less is considered a slow charge, while 20 amps or above is generally considered a fast charge.
If you use a lithium charger on a lead-acid battery, it will supply a constant voltage to the battery for as long as it is able to. There are multi-mode chargers that can be used to charge any kind of battery and that have features to protect the battery and prolong its life.
No, you can't charge a 12 volt battery with a 12 volt power supply because the charging voltage always needs to be greater than the battery voltage (12 volts).
The target voltage for a 24 volt charger for AGM or some flooded batteries is 2.4 to 2.45 volts per cell, which is 28.8 to 29.4 volts.
Three Stage Battery ChargingThe target voltage for a 12 volt charger for AGM or some flooded batteries is 2.4 to 2.45 volts per cell, which is 14.4 to 14.7 volts. Some flooded cells will tolerate over 15 volts.
Do not fully charge lead acid batteries more than once per 24-hour period to maximize your battery's life.
