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Thread ID: 142349	2016-06-15 22:16:00	car battery question	1101 (13337)	PC World Chat

Post ID	Timestamp	Content	User
1422016	2016-06-19 20:39:00	Just make sure if using a solar panel for this that there's a diode to prevent battery discharge overnight - often built into the panel but not always. Without it they use more power than they give. Also some of the cheapo ones are not regulated at all, they just rely on not being able to produce enough current/voltage to do any damage to a car sized lead acid battery. If you hooked them up to a smaller capacity battery they might actually manage to overcharge it.	dugimodo (138)
1422017	2016-06-19 22:28:00	'Tis' true . Overcharge is usually very bad but modern alternators will under certain circumstances push out more than 17 VDC to charge the battery and stay ahead of accessory use even before the vehicle moves from parked . I've monitored my solar panel and it immediately goes to 16 . 5 and then modulates down to 13 . 6 where it stays . A 12 volt battery is not really 12 volts, more like 13 . 1 - 13 . 8, fully charged depending on the ambient temperature . In fact many Chrysler econo boxes use battery temp for charge regulation . If in question whether the panel has a diode, it will get pretty warm while it sucks power from the battery that it just floated if it doesn't have a diode . That staored electrical energy would have to get converted to the lowest common denominator - heat .	SurferJoe46 (51)
1422018	2016-06-19 23:24:00	And you are right Joe, "dashboard" sounds pretty good to us too.	Richard (739)
1422019	2016-06-22 01:09:00	those small 1 . 5watt etc solar panels so almost nothing unless its a really small battery . firstly the wattage rating is derived from there voltage and current output, but their voltage output is up around 18v or so . so at max it produces 0 . 08 amps or 83mA . now thats also only at max in full sunlight . any shading on it will reduce its output quite a bit . NZ typically has lower sunshine hours hence solar is less effective here than other countries like aussie . even if you get good sunshine its only for a limited time per day . so really you only get 50% output, that makes it 41mA and then its only for lets be generous at 8 hours a day, so only 1/3 of the time compared to a mains charger . so the equivalent charge rate, if its was spread over 24 hrs like a mains charger, is a mere 13mA most trickle chargers are 200-500mA . so the overall charge these solar panels deliver is so small it really doesn't do anything . in practice i found you need at least a 10watt, preferable with a pwm or mppt charger which can increase the solar output by 30-50% .	tweak'e (69)
1422020	2016-06-22 03:49:00	That might pencil out as you say, but anecdotally I had a very bad battery in my "spare Blazer" for a few years that would not, could not be depended upon to start at any time and I had a buddy loan me one of his and as the story goes, I could start that Blazer, bad battery and all pretty much all the time if I didn't have to crank too long to get it to fire up . The spare Blazer now has become my number one (NZ= #1Sillimeter) daily driver here in Montana and still has that charger on the dashboard, albeit with a much better battery . But there is a vehicle "Keep Alive" current draw from the ECM 24/7/365 that can kill a battery over the winter of non use by snowbirds who live here in the summer months and go south for the winter . Those cars seem to need new batteries every spring . Last year I told my neighbor/snowbird to put one of them in his 1988 Thunderbird and when he got here it fired right up like he parked it there yesterday . Just saying . . . . . . . . . . . . . . . . . . . .	SurferJoe46 (51)
1422021	2016-06-22 04:05:00	That might pencil out as you say, but anecdotally ........... keep in mind "sunshine hours". NZ tends to be cloudy and has reduced average sunlight levels. something i ran into when comparing solar in Australia.	tweak'e (69)
1422022	2016-06-22 04:11:00	SoCal was very sunny, and that's for sure --- but Montanna has seriously shorter daylight in winter, so there's that too . I'd guess that here in winter we get 75% sunny --but shorter --days at the 46th parallel . BTW: are you up at an ungodly hour in Upsidedown Land? It's 21:00 here, Tuesday evening .	SurferJoe46 (51)
1422023	2016-06-22 04:20:00	SoCal was very sunny, and that's for sure --- but Montanna has seriously shorter daylight in winter, so there's that too. I'd guess that here in winter we get 75% sunny --but shorter --days at the 46th parallel. BTW: are you up at an ungodly hour in Upsidedown Land? It's 21:00 here, Tuesday evening. nah mate its afternoon tea time here. its been raining all day so i'm putting my feet up today.	tweak'e (69)
1422024	2016-06-22 05:27:00	That might pencil out as you say, but anecdotally I had a very bad battery in my "spare Blazer" for a few years that would not, could not be depended upon to start at any time and I had a buddy loan me one of his and as the story goes, I could start that Blazer, bad battery and all pretty much all the time if I didn't have to crank too long to get it to fire up . The spare Blazer now has become my number one (NZ= #1Sillimeter) daily driver here in Montana and still has that charger on the dashboard, albeit with a much better battery . But there is a vehicle "Keep Alive" current draw from the ECM 24/7/365 that can kill a battery over the winter of non use by snowbirds who live here in the summer months and go south for the winter . Those cars seem to need new batteries every spring . Last year I told my neighbor/snowbird to put one of them in his 1988 Thunderbird and when he got here it fired right up like he parked it there yesterday . Just saying . . . . . . . . . . . . . . . . . . . . I think the technology and charging pattern of a advanced solar panel can greatly enhance/maintain the charge status of the car's battery . According to a comment ( . instructables . com/id/How-to-charge-a-12-volt-battery-using-Solar-Power-1/" target="_blank">www . instructables . com) (instructables article) Some panels can periodically output a increased charge (i . e . shock charge) to prevent sulphation (and I think prevent chemical reversal . . . to help maintain equilibrium) . So a solar panel (it's controller) may not always be in trickle mode . . . . Hence with a alternator's regulator or Honda's ELD system ( . gonzostoolbox . com/KnowledgeFolder/HondaELD . html" target="_blank">www . gonzostoolbox . com) it seems to better maintain a status at 13 . 2V as mentioned in the comment - and as you mentioned earlier . - Talking about battery boosting - Maybe enhanced spark/ignition timing may help? Heard of Lectran? I with a crowd of others were amazed when this American bloke use to promote them at our local flea markets around '76 - '78 every week . Stick it on the HT lead and would easily start up (after demonstrating poor car starting) his large Cadillac or Lincoln, and a large 60's Mustang . He use to lecture on for about an hour the virtues of always starting a hard to start car with Lectran . . . .	kahawai chaser (3545)
1422025	2016-06-22 06:15:00	keep in mind "sunshine hours". NZ tends to be cloudy and has reduced average sunlight levels. something i ran into when comparing solar in Australia. You don't live in Hawkes Bay do you!!! :devil Ken	kenj (9738)
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