I have a deep cycle marine battery that is no good. When I bought it I did not know they make ones that require a trickle charge and ones that do not. I had used mine for some time before I discovered this. The ones that do not require a trickle charge are quite a bit more expensive, if I recall correctly. Was this always the case, i.e., that they made two kinds? I had bought one many years ago I gave to a friend who was very knowledgeable about electronics. He just had it set outside without any charge. He would have known if it required a trickle charge. Either they didn't make the trickle charge ones way back then, or maybe I had just lucked out and bought the kind that does not require a trickle charge. Tim, since you can get 30 hours of a battery before it needs recharging, maybe the cheapest thing for me to do is buy another battery for my pickup. Then when I do my 80 mile per day driving I can put in the one that I had used for the laptop to charge it up. Since you can get 30 hours I am assuming there would be enough charge left to start the 2004 Ford Ranger motor. Stan On 3/15/2015 12:29 PM, Jim Waters wrote: > I have never had an issue with the Deep Cycle Marine that I use. I have it > in a carrying case. Yes - you need to be careful when transporting it. The > out gassing issue has never been a concern for me. Not sure what you mean > by 'overloading the cigarette lighter circuit'. > > Jim > > -----Original Message----- > From: az-observing-bounce@xxxxxxxxxxxxx > [mailto:az-observing-bounce@xxxxxxxxxxxxx] On Behalf Of Dan Heim > Sent: Sunday, March 15, 2015 12:05 PM > To: az-observing@xxxxxxxxxxxxx > Subject: [AZ-Observing] Re: Recharging > > Stan, > Figuring on a good day you'll get 6 hours of solar charging (in an unshaded > area on a clear day), that would provide 30 watt-hours ignoring conversion > efficiency losses. Your typical car battery holds about 1000 watt-hours, so > you wouldn't be able to give it much of a charge. > > I'd be a little wary of having an acid filled car battery sitting on the > floor in my car and charging from the cigarette lighter, although that could > add some more capacity. I'd be worried about the charging current > overloading the cigarette lighter circuit, not to mention out-gassing (if > it's a non-sealed battery). > > But a small UPS of the correct capacity, with a built-in charge controller > might do the trick. They are totally sealed. But you'd still have to check > the capacity and charging current so it doesn't blow fuses in your car. > Haven't searched online, but I'm pretty sure you could find with with a > cigarette lighter adapter. The standard UPSs usually charge from 120 VAC. > > Dan Heim > > > On 3/15/2015 11:51 AM, Stan Gorodenski wrote: > >> A few years ago I had asked a question of how long a 12V battery would >> last to power a laptop on a night of observing. I have a related >> question. The reason I ask it is because I know nothing about >> electronics or electricity. >> >> I need to be away from power for days at a time. I have a 5 watt solar >> panel I bought years ago. If I run a laptop for about 3-4 hours a >> night with an inverter, would this 5 watt solar panel be enough to >> charge a car battery (not a battery in my pickup but a separate >> battery) with the amount that was used by the laptop? I doubt it and >> probably need a larger panel for this to work, but maybe it would have >> to be too large to be practical. >> >> Alternatively, I would be driving about 80 miles per day. Can one >> charge a separate car battery plugged into a cigarette lighter? >> Stan >> >> > > -- > See message header for info on list archives or unsubscribing, and please > send personal replies to the author, not the list. > > > > -- > See message header for info on list archives or unsubscribing, and please > send personal replies to the author, not the list. > > > > > -- See message header for info on list archives or unsubscribing, and please send personal replies to the author, not the list.