# How long (in hours) will a 6 Amps LED light last if powered only by 12V 18Ah Lead Acid Battery only

I have assembled a 300 units of 3650 LED lights which draws a total power of roughly 6 Amps (130Watts) and I want to power it using a 12V 18Ah Lead Acid Battery.

My question is, how long or how many hours the assembled light will last before the battery gets fully discharged?

Is there a certain formula that I can use to get the total hours consumed?

• 130 watts at 6 amps requires 21.67 volts, not 12v. So you have some "how is this going to work at all" engineering to do, or mistakes to correct, before you can make this calculation. If you involve a boost converter, you have to consider its efficiency. Aug 15 '17 at 11:48
• You should include the minimum voltage needed by your LED array in your question. If you give some more details, you get better answers.
– Uwe
Aug 15 '17 at 17:19
• As Mr. Stratton says, the load seems not to be a 12v one. You will need a voltage multiplier. Based only on power consumption, if the load is 130 W and battery is 12v*18Ah=216Wh, the battery will fail before 216Wh/130W=1.6 hours Oct 31 '17 at 16:06

The capacity will also change depending the how much current is drawn, and the temperature. Here's an example from a Panasonic battery datasheet: 