Anybody here use a battery tender during the winter??

[69wannabe]

Just wondering if anybody besides me uses the little battery tenders to keep their battery charged while it's waiting for better weather? I bought the battery tender jr. and it works good and I figure this helps the charging system to keep the alternator from working so hard to charge the battery back up after sitting for weeks at a time without being started. Works good on extra batteries to keep them charged up if they are just sitting around too.

[Ghoste]

I do and its an excellent idea.

[Cooter]

Yep. Best money I've spent. Mine keeps up to 4 batteries hooked in Series, charged.

[Dans 68]

Another yep.

Dan

[cjw916]

I use a Battery Tender Jr. (750mA) on my '68 Charger. I use it year 'round, as I have a Kenwood stereo in the glove box, with a small 2-channel amp for the front 4" speakers, a large 2-channel amp for the rear 6"x9" speakers, and a large mono amp for the twin 10" sub-woofer enclosure I have in the trunk. I leave it plugged-in whenever the car is parked. I like to listen to the stereo when working on the car (non-electrical projects) so it really gets a workout! Thing has lasted over 10 years, and the battery must be close to that old, also. I keep waiting for the battery to die, so I can upgrade to a new Optima red-top, but the thing just won't die!

I first got it because my tic-toc clock used to slowly drain my battery. I've since replaced the voltage draw with a tachometer, never really loved the tic-toc-tach & saw the inexpensive upgrade as a way to remove the battery drain I never cared for (mine did not keep accurate time).

Battery Tender really is a solid investment.

I just cringe every Spring when I see my neighbor put the trickle charger on his '66 Chevelle, then I remember, eh, it's just a BowTie POS, who cares? Lol.

[Dodge Don]

YEP 

[A383Wing]

Yea..I do as well, got 2 cars each hooked up to one tender...the ones I got are Schumacher brand

and I got a little Harbor Freight one for the other 66 in the house garage

[471_Magnum]

I use one of these:
http://www.autometer.com/cat_accessoriesdetail.aspx?vid=1

Seems to do a really good job. I've had one for years. I've had it replaced under warranty at least once. It will NOT recharge a dead battery though. If the battery voltage is really low, it will fault out.

[Troy]

I have one full size Battery Tender and three Juniors. It's nice because they have a voltage monitor and only charge when needed. I don't have to remember to check them myself! I disconnect the negative cables from the battery but they still discharge a slight amount. This way all my cars are ready to go on the first nice day of spring (or in the middle of winter if I just want to run them for 15-20 minutes for exercise.

Troy

[bill440rt]

Another vote here.
I've got a 4-bank tender keeping 4 batteries going over the winter. I remove the batteries from the cars, lawn tractor, trailer, etc & keep them on a corner of my workbench hooked to the Tender.
I really need another one, I've got 6 batteries total that need to be kept charged so I may just pick up another one.

[4cruzin]

Pretty much need to have one!  I have 4 auto and 2 jetski batteries that need to be juiced through the winter.   

[cjw916]

I never thought to 'daisy-chain' batteries in parallel, like that? I did go to college for Mechanical Engineering and I had many Electrical Engineering classes, but I just never thought to do it like that? Good idea for power sports batteries! Does anyone out there (smarter than me) know if different CCA batteries in parallel will 'draw' off each other? I certainly do know that they'll charge at different rates, only because the larger batteries are 'seen' by the voltage source as a larger Ohm resistance P=V*I, V=I*R, P=I^2*R. So. . . I think when you daisy-chain different CCA batteries in parallel, the smaller batts will draw off the larger, but, once charged, I don't think it matters, I mean, the larger will drain to charge the smallers, then the Tender will charge the largest CCA battery last.

I do know that in an automobile, if you care to run dual batteries in parallel, you must make sure that the batteries are exactly the same. I though about installing dual Optima AGM batteries in my trunk, because I have a big stereo with 3 amplifiers, that can draw a lot of power, and two batteries will give you 2x the 'power bucket' to draw from. AND, two batteries will give you double the CCA as one battery will, Amps add when in parallel, so two 800CCA batteries will effectively give you 1,600CCA. (You'll melt your battery cables before you'll ever use that many Amps!)

But, the question remains, 4 different CCA batts, is it OK to winter them in parallel with one float charger like above?

[Pete in NH]

You can float charge lead acid batteries at something a little less than full fast charge voltages. I don't see anything wrong with tooking several batteries in parallel as long as they are fully charged before doing so. Then they are just there on a maintenance float charge. If the normal fast charge voltage is 13.8 to 14.4 Volts, something like 13.2 to 13.8 would be okay for floating. It's always best though to refer back to the battery makers specifications on float charging if that information is available. This kind of float charging is a good way to prevent sulfation. I would also refer back to the battery tender makers instructions about how many batteries they can support this way. If you put too many batteries on it too much current draw might trigger a fault light.

[4cruzin]

Well now you have me curious as well. . . All I know is it is working!  Green light on the tender!   

[69wannabe]

Another vote here.
I've got a 4-bank tender keeping 4 batteries going over the winter. I remove the batteries from the cars, lawn tractor, trailer, etc & keep them on a corner of my workbench hooked to the Tender.
I really need another one, I've got 6 batteries total that need to be kept charged so I may just pick up another one.

That reminds me, I have got to take the battery out of my lawn tractor and charge it since it hasn't been touched since early september!!

[cjw916]

I agree, starting 'near' fully charged, it should be fine. My little Jr is only 750mA (.75A) but my dual gang box is 1.25A per channel, I think the 4 gang Battery Tenders are 1.25A per Channel, too. As long as the batteries are near full charge to begin with, even though they are of varying AmpHour capacities, they should all 'float' fine in parallel.

I do believe what's really happening is the largest battery is drawn upon by the smaller batteries, and the Tender is really only charging the biggest battery.

I have been pretty rough on my little guy. I left my amplifiers on once, drained my battery D E A D overnight. Ooops! Put it on 6Amps for 6 hours, then 2Amps for overnight, then on the little Junior .75A for about 2 or 3 days before it went green, but it was 'all good' after that. The things can really pump out a lot of voltage without dying!

[Troy]

Good timing - Eastwood has them on sale right now!

Troy

[oldcarnut]

I use these on the boat batteries and extra car battery.  On sale now at Harbor Freight and take another 20-25% off with the coupons.
http://www.harborfreight.com/automatic-battery-float-charger-42292.html

[RAC95054]

I use one on each of my cars.  Far cheaper then buying a new battery earlier than you should have to.