The Ford Barn

MikeK · 02-05-2014, 11:41 PM

A group one 6V battery has a storage capacity of about 80 amp-hours when new. After a few years that is down to ~60 amp-hours. You do not want to ever draw a battery down much below 50% charge, especially if you want it to crank reliably for a re-start.

If you discharge at a 10 amp rate x 3 hours you will use 30 amp-hours. Thus, you can safely go about 3 hours, 4 if the battery is new and fully charged. You will, of course, either need to put it on an external charger or drive at least TEN HOURS the next day with the lights off if your charge rate is 3A as you say.

02-05-2014, 11:41 PM	#3
MikeK Senior Member Join Date: May 2010 Location: Windy City Posts: 2,919	Re: How Long 'Till Lights Out? A group one 6V battery has a storage capacity of about 80 amp-hours when new. After a few years that is down to ~60 amp-hours. You do not want to ever draw a battery down much below 50% charge, especially if you want it to crank reliably for a re-start. If you discharge at a 10 amp rate x 3 hours you will use 30 amp-hours. Thus, you can safely go about 3 hours, 4 if the battery is new and fully charged. You will, of course, either need to put it on an external charger or drive at least TEN HOURS the next day with the lights off if your charge rate is 3A as you say.