Will a 100 w solar panel trickle charge a 48 V battery?

A 100 W solar panel can potentially trickle charge a 48 V battery, but there are some factors you need to consider:

Output voltage: Ensure the solar panel's output voltage is compatible with your 48 V battery.

You may need a solar charge controller to regulate the voltage and current to the battery, as solar panels' output voltage can vary depending on sunlight conditions.

Charge controller

For a 48 V battery, use a charge controller that is specifically designed for 48 V systems. This will ensure optimal charging and help prevent overcharging or undercharging the battery.

Charging current

To calculate the charging current, divide the solar panel's power (in watts) by the battery voltage (in volts). For a 100 W solar panel and a 48 V battery, the charging current would be:

Charging current = Power (W) / Voltage (V) = 100 W / 48 V ≈ 2.08 A

This is a relatively low charging current, so it may be considered a “trickle charge” for a large-capacity 48 V battery. However, if the battery capacity is small, this current may not be considered a trickle charge.

Battery capacity and charging time

Consider the battery's capacity (measured in amp-hours, Ah) to determine how long it will take to charge using the 100 W solar panel. A larger battery will take longer to charge with a 100 W solar panel.

For example, if you have a 48 V, 100 Ah battery, the total energy capacity is:

Energy capacity = Voltage (V) × Capacity (Ah) = 48 V × 100 Ah = 4800 Wh

Assuming the solar panel produces 100 W consistently (which it likely won't due to varying sunlight conditions), the charging time would be:

Charging time = Energy capacity (Wh) / Power (W) = 4800 Wh / 100 W = 48 hours

Keep in mind that this calculation is a rough estimate and assumes ideal conditions. In reality, charging time will likely be longer due to varying sunlight conditions, solar panel angle, efficiency losses, and other factors.

In summary, a 100 W solar panel can trickle charge a 48 V battery, but you will need a compatible charge controller and should consider the battery's capacity, charging current, and charging time.