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Luke
15-03-2002, 08:31 AM
Does anyone have any ideas on charging deep cycle batteries quickly. I've looked into solar panels and for a 10w panel which is too big in dimensions for a tinny anyway(about metre x 40cm) I figured it will give .83 amps per hour and the electric will use 36 amp/hours at full throttle. To me even as a top up this isn't feasible. Does anyone use these and what do you think? It won't be a problem ordinarily but on long trips away from power sources what does everyone do?
Cheers Luke

Fitzy
15-03-2002, 09:06 AM
Been down this path yonks ago. My advice is to make sure you've got paddles with you. ::)

Jack_Lives_Here
15-03-2002, 10:34 AM
Yeah the solar panels just can't pump enough juice in. Had a look at the chargers on the attached link a while ago. Seem very good but along with that comes the cost.

http://www.baintech.com.au

That new rig of yours is gunna go mighty fine behind that house boat at Hinchinbrook in Sept. ;D ;D

All the best
Dave

Luke
15-03-2002, 11:30 AM
So no genius generator/alternator setups?? :D

Kerry
15-03-2002, 01:53 PM
Nope, solar panels won't even come close and really there's no magic either.

BTW, that 10W output for a panel being a metre by 40cm sounds a bit wierd #??? , Some fairly common 75 watt panels are 1280*500 and I'm running 46W panels which are 820*500.

The other thing is I don't believe a deep cycle battery should be charged quickly (but don't quote me on that one).

On trips a reasonable size panel however should recharge a battery over a full day (assuming there's sun of course #;D), just requires an extra battery (or so).

I have a spread sheet which might give you some insight into just what size panel v battery size to run whatever for whatever period of time if you require.

Cheers, Kerry.

Luke
15-03-2002, 04:05 PM
Hey Kerry,
yes those dimensions was the info I got from supercheap on a 10 watter at $159 whereas another mob were offering a 40 w panel at 40cm x 60cm that gives 2.3 amps per hour so you tell me????? Just out of interest though how big are you talking about when you say reasonable size panel and how many amp/hour battery are you talking to be able to get a full charge through the sun in a day? Must be a big one. Either way I'm not going to bother. Thanks all.
Luke

Luke
15-03-2002, 04:11 PM
Hey Kerry,
don't worry about the conversion chart. Basic maths mate. Do it in me noggin ;D
Cheers Luke

Fitzy
15-03-2002, 04:20 PM
Luke,
Ring Russ at A1 Solar. Think they're at Wynum or somewhere around that area from memory. He ran thru some ideas with me several years ago. He recons it's possible, but the cost is pretty big.

Luke
15-03-2002, 04:31 PM
Thanks Fitz,
I'll have a yak to him but I reckon your right. The costs would probably deter me at this stage. :-/
Cheers Luke

Kerry
15-03-2002, 05:07 PM
Hey Kerry,
don't worry about the conversion chart. Basic maths mate. Do it in me noggin ;D
Cheers Luke


I suppose the sun's inclination/factor (or whatever they call it) comes into your noggin as well as a few other things come into the result.

The offers still there if you change your noggin (mind).

Cheers, Kerry.

Kerry
15-03-2002, 05:23 PM
Ok Like I've found the original source so you may feel better using it now #;). Like I said it may be useful it may be not.

I'm not all that sure if the URL will work as it looks like about 300 characters long but we can only try.

http://bpsolar.custhelp.com/cgi-bin/bpsolar.cfg/php/enduser/std_adp.php?p_sid=Ye2X53ag&p_lva=&p_faqid=180&p_created=972955110&p_sp=cF9ncmlkc29ydD0mcF9yb3dfY250PTM3JnBfc2VhcmNoX 3RleHQ9YXJyYXkgc2l6ZSZwX3NlYXJjaF90eXBlPTMmcF9wcm9 kX2x2bDE9fmFueX4mcF9wcm9kX2x2bDI9

If that doesn't work then

http://bpsolar.custhelp.com/cgi-bin/bpsolar.cfg/php/enduser/std_adp.php?p_sid=Ye2X53ag&p_lva=&p_faqid=180&p_created=972955110&p_sp=cF9ncmlkc29ydD0mcF9yb3dfY250PTM3JnBfc2VhcmNoX 3RleHQ9YXJyYXkgc2l6ZSZwX3NlYXJjaF90eXBlPTMmcF9wcm9 kX2x2bDE9fmFueX4mcF9wcm9kX2x2bDI9

If all fails it's Answer Id 180 on the BP Solar Knowledge Base and the file (ZIP) is an attachment to that query.

Cheers, Kerry.

Luke
16-03-2002, 05:23 AM
Hey Kerry(oh fiesty one)
ok yes noggin works -basic electrical theory P=EI
eg. being Power=Voltage x Current
being 40w =12v x Unknown
being 40 over 12
result being 3.3 amps intake per hour maximum. If my electric draws 35 amp/hour with a 105amp/hour battery and I use it at full it will be flat in around 3 hours and even around half it will be flat in around 6 hours. I just don't think I need a conversion chart to tell me that Kerry and if the suns not out(btw you won't get more than 3.3 per hour even if the suns knocking on your door) then none of this is relevant anyway. Lets say I get my 3.3 an hour and you said it yourself' solar panel wont come close"(atleast on a tinny anyway) then it would take around 31 hours to charge full from flat. Like I said basic maths mate.PS will have a look at those links-not being ignorant.
Cheers Luke

Luke
16-03-2002, 06:31 AM
Neglected the loss through wiring and diodes lose about a third of the amps so thats where I got the first figure of 2.3 so actually the equation should read 40 over 17 as you need 14-15volts to run 12 volt battery and loss in previously mentioned wiring and diodes approximately. Also Kerry when I say quickly I'm wondering what others used and if they had any ingenious inventions. But you are right when you say you can't charge them quickly or not as quickly as a normal battery anyway. It is not physically possible as they have less plates but thicker plates therefore electrolites are charging a smaller surface area.
Cheers Luke

Kerry
16-03-2002, 12:09 PM
Not sure where this maximum amps come from as it's dependant of the panel/s. Why are you limiting things to 40watts ???.

Oh and for your noggin don't forget to factor in the cycling capacity 'cause you should know that no battery will cyle all the way to zero (as you are suggesting). Of course a deep cycle will handle the bigger dis-charge over a normal battery but no battery in this instance is designed to be fully run down, won't live long at all.


Cheers, Kerry.

Luke
16-03-2002, 01:29 PM
Kerry,
Not limiting to 40w. Just an "eg!". How big a panel/or how many would you suggest putting on a tinny seriously if at all. Allright I said flat to full and deeper cycle batteries are more capable of this. Flat being used loosely( sorry if you didn't understand that) If you do the sums you'll see where the maximum capability amp output comes from for a 40w panel in full sun without invertors/regulators and if you do the same sum with say a 70 w panel you will obviously have a higher amp output. I'm no battery expert but like I said basic electrical theory gives me a better than ruff idea on what I need to know. Anyway like I said I'm not going to worry about solar panels.
Cheers Luke

Kerry
16-03-2002, 01:43 PM
I think the feasability of actually putting panels on a tinnie has already been eliminated. But if it's a case of being out and about for a few days then panels "might" work for recharging on a rotation basis. But it's also already been said that the cost might/will be a bit scarey.

If you get over this inhibition about this spreadsheet and plug the numbers in you'll probably have a reasonable answer but what makes me think you don't really want to do that.

Cheers, Kerry.

Luke
16-03-2002, 02:50 PM
I'll check it out. No worries.
Cheers Luke

Luke
16-03-2002, 03:09 PM
Well Kerry,
I had a look at the charts and I got
40w = 16.9volts x 2.34amps. Isn't that close enough to what I said using me noggin instead of looking at a chart. I was .01 out on the Voltage and that was just a guess and .01 out on the amps as I didn't round up. What are you trying to tell me mate. ??? Admittedly the dimensions I gave were slightly out on the larger side mind you and that makes it even less feasable.
Cheers Luke

Kerry
16-03-2002, 05:57 PM
So how many panels did it think you might need to re-charge your 105a/h battery in a useable time. Might be a few I'd imagine ???

Cheers, Kerry.

Luke
16-03-2002, 06:00 PM
Yeh I think this one is a lost cause. I'd have to build a roof on the tinny. ;D
Cheers Luke