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jmo_54729
10-07-2005, 01:14 PM
Has anyone ever attempted to connect a battery maintainer to more than 1 battery. In other words,
I'd like to take 3 12-volt batteries, (all charged) and
connect them in parallel, then connect the battery maintainer to all three, so that I don't have to keep rotating through the batteries all winter, or buy 3 battery maintainers. Battery maintainers are the little "wall wort" power supplies that keep batteries charged up when you're not using them.

Anyone see a problem with doing this?

Jim

lakes Rick
10-07-2005, 01:29 PM
I "think" I have seen maintainers designed to charge more than one battery at a time.......

Psheehy
10-07-2005, 09:19 PM
You can hook them up in parallel to see. Nothing to loose. Measure the voltage across the battery terminals. Each battery should read close to 14 volts if it is indeed charging. The amps (rate of charge does not matter to you). The unit might get overloaded though carrying the load of 3 batteries & quit if the state of charge on any of the batteries requires the charger to work too hard. Paul Sheehy Douglas Battery Winston-Salem, NC

PointTaken
10-07-2005, 09:27 PM
Has anyone ever attempted to connect a battery maintainer to more than 1 battery. In other words,
I'd like to take 3 12-volt batteries, (all charged) and
connect them in parallel, then connect the battery maintainer to all three, so that I don't have to keep rotating through the batteries all winter, or buy 3 battery maintainers. Battery maintainers are the little "wall wort" power supplies that keep batteries charged up when you're not using them.

Anyone see a problem with doing this?

Jim
3 batteries? What kind of system do you have in that boat? :confused: Feel free not to answer, as I may feel obligated to upgrade mine if it sounds good :D

gregg
10-14-2005, 10:22 AM
Has anyone ever attempted to connect a battery maintainer to more than 1 battery. In other words,
I'd like to take 3 12-volt batteries, (all charged) and
connect them in parallel, then connect the battery maintainer to all three, so that I don't have to keep rotating through the batteries all winter, or buy 3 battery maintainers. Battery maintainers are the little "wall wort" power supplies that keep batteries charged up when you're not using them.

Anyone see a problem with doing this?

Jim
I have 2 batteries in parallel and have had no problems at all. I installed and hard wired a Guest 5x2 bank marine charger in my 2002 Maristar 210. 5x2 simply means it charges at 5 amps per bank(battery). A battery's biggest enemy is setting in a state of partial or complete discharge. After a day of running the stereo hard, when I get back to the shop I just pull the cord out and plug the charger in. Next morning both batteries are fully charged and ready to go. Also setting idle during the winter months, I plug it in every couple of weeks to keep the batteries fully charged, or you can leave it plugged in all the time. If you look in Bass Pro's Marine catalog they also have 3 bank chargers for your application. If you are using Marine batteries, make sure you get a marine charger, they are different that a normal starting battery charger.

Leroy
10-14-2005, 10:32 AM
If the same type you will probably not have any problems however if different types or sizes you could. Technically you should have some isolation for each battery. Depends if there is a different "holding voltage" in each battery.

You could do that by putting a 30-100 ohms several watt resistor from Radio SHack in line with positive lead to each battery.

hillbw
02-06-2009, 03:44 PM
Minn Kota makes a MK-35 3 bank battery maintainer. Mfr. # 1820350, Model # 2259909. Sells for around $100.00. This will maintain three batteries at the same time. You just have one unit that has connections to all three batteries. This is a lot better than having one unit for each battery. This unit comes in 6 or 12 volt.

brucemac
02-06-2009, 03:50 PM
like leroy said not recommended, especially if they are different.

why don't you just pick up a second 2-bank battery tender? they're like $60 or so I think on amazon.

Sodar
02-06-2009, 04:46 PM
Minn Kota makes a MK-35 3 bank battery maintainer. Mfr. # 1820350, Model # 2259909. Sells for around $100.00. This will maintain three batteries at the same time. You just have one unit that has connections to all three batteries. This is a lot better than having one unit for each battery. This unit comes in 6 or 12 volt.

Cool deal! Anything for a 2-bank?

Sodar
02-06-2009, 04:47 PM
like leroy said not recommended, especially if they are different.

why don't you just pick up a second 2-bank battery tender? they're like $60 or so I think on amazon.

Naw, it would be better to have one unit that you could mount that was connected to all the batts. Just pull in the garage and plug an extension cord in... next time you took off, the batts would be ready for action!

ejg333
02-06-2009, 07:25 PM
Minn Kota makes a MK-35 3 bank battery maintainer. Mfr. # 1820350, Model # 2259909. Sells for around $100.00. This will maintain three batteries at the same time. You just have one unit that has connections to all three batteries. This is a lot better than having one unit for each battery. This unit comes in 6 or 12 volt.
I have this unit it's under the observers seat in my 197 only using it for 1 battery right now but I am going to expand to 2 batteries in the near future.

TMCNo1
02-07-2009, 04:19 PM
They make them for more than one battery, http://batterytender.com/default.php?cPath=11_2&osCsid=c1801f7d7604e17536656b09889efdfc

chico
02-21-2009, 02:02 PM
Don`t forget to use a battery desulphanator to get it back to new condition.

TX.X-30 fan
02-21-2009, 06:26 PM
Am I missing something, I have a starter battery and 2 other stereo batteries. I hook to the first stereo battery in the line and it trickle charges to the second one and I use an echo charger off the first stereo battery to bleed back to the starter so it all charges off the one stereo battery i have on the charger.

I have not put a tester on the one stero battery that is not direct to the trickle charger but I see no reason to believe its not charging too. I know the starter is because i have a green flashing light on the echo charger that lets me know if its full or taking some charge from the stereo battery. Been bullit proof for three years now so I assume it works.

Cloaked
02-21-2009, 08:17 PM
Am I missing something, I have a starter battery and 2 other stereo batteries. I hook to the first stereo battery in the line and it trickle charges to the second one and I use an echo charger off the first stereo battery to bleed back to the starter so it all charges off the one stereo battery i have on the charger.

I have not put a tester on the one stero battery that is not direct to the trickle charger but I see no reason to believe its not charging too. I know the starter is because i have a green flashing light on the echo charger that lets me know if its full or taking some charge from the stereo battery. Been bullit proof for three years now so I assume it works.You bring a good point.


A Battery Tender is a float charger.

The difference between a float charger and a trickle charger is that the float has circuitry to prevent overcharging. It senses when the battery voltage is at the maximum level and temporarily shuts off the charge (floats voltage at zero or a very minimal charge until it senses that the battery output voltage has fallen, then resumes charging ). You can keep it connected indefinitely.

A trickle charger, on the other hand, will charge no matter whether the battery is fully charged or not. So it needs to be connected and disconnected periodically. If left in place too long it'll eventually boil the electrolyte out of the cells or damage the plates. Trickle chargers will work to keep the battery charged if used once a month or so for a day or 2, but the float chargers can be left connected indefinitely without potential harm to the battery.

TX.X-30 fan
02-21-2009, 10:17 PM
My mistake, I use a float charger that is designed or works with AGM batteries. Would the float charger not look at the two stereo batteries as one and charge accordingly. Hooked up in parallel i mean.

Cloaked
02-22-2009, 07:29 AM
My mistake, I use a float charger that is designed or works with AGM batteries. Would the float charger not look at the two stereo batteries as one and charge accordingly. Hooked up in parallel i mean.
Yes.......

jamica joe
11-04-2010, 11:28 AM
I have always thought that a float and trickle charger were the same animal... What is the difference, and which should I use for winter storage for jet ski???

jamica joe
11-04-2010, 12:24 PM
bump bump bump

03geetee
11-04-2010, 03:58 PM
bump bump bump

I use a Battery Tender Jr for my SeaDoo and its great. I winterize my ski then just plug in the nice attachment that is already on my battery so I dont have to mess with taking it out each time and plug it in to the wall done.

Really that simple same battery for several seasons versus constantly buying new ones.

JTR

Cloaked
11-04-2010, 05:01 PM
I have always thought that a float and trickle charger were the same animal... What is the difference, and which should I use for winter storage for jet ski???A trickle is a constant charge. At some point, the battery is full and an unattended trickle doesn't know when to stop. The Battery Tender has a microchip smartboart that knows when to stop the charge, maintains the proper charge, and by this, cares for the longevity of the life of the battery. I use the BT year-round.

Battery Tender

www.batterymart.com (http://www.batterymart.com)

.

Gamble
11-12-2010, 11:33 AM
yep, use mine year round, have 2 of the batt tender jr's. They work great and I use them for my 4 wheeler and motorcycle. Seems like the battery is always ready to go and they seem to last longer.

YTW
12-06-2010, 12:49 PM
So why is it that a truck can sit for three months and start right up, by a boat sits for 3 weeks and needs the battery charged. I understand that a battery tender will prevent this, but why can't the same technology on the truck work for the boat?

Thrall
12-06-2010, 03:35 PM
So why is it that a truck can sit for three months and start right up, by a boat sits for 3 weeks and needs the battery charged. I understand that a battery tender will prevent this, but why can't the same technology on the truck work for the boat?

If your boat needs a jump start after sitting for a couple weeks then there's something wrong with the boat. There's something draining the power. 'The need for charging the boat batteries stem mostly from those with big sound systems that use mo' power in a day than the alternator can re-charge. Or those that spend alot of time with the engine off and the stereo on. The need for maintaining the battery(s) charge just extends the life of the battery.

ctjahn
12-06-2010, 05:55 PM
They make them for more than one battery, http://batterytender.com/default.php?cPath=11_2&osCsid=c1801f7d7604e17536656b09889efdfc

I use two of these to maintain my fleet (moving them around because the racecar trailer with two sits outside, the boat and other batteries are inside disconnected, the racecar batteries are in the cars with a number of pigtails): http://batterytender.com/automotive/battery-tender-plus-12v-at-1-25a.html

If I wasnt so lazy, or cheap, I would disconnect and remove all the batteries from all the vehicles and store them in a warm place with a fleet charger: http://batterytender.com/automotive/5-bank-charger-12v-at-2a.html

I have had good luck with them and used them for years....(but you have to watch them) Just my experience.... I am no expert but I do have a Assoc in Electrical Engineering from MSOE and I didnt stay at a Holiday in Express last night...

Cj

YTW
12-06-2010, 06:31 PM
If your boat needs a jump start after sitting for a couple weeks then there's something wrong with the boat. There's something draining the power. 'The need for charging the boat batteries stem mostly from those with big sound systems that use mo' power in a day than the alternator can re-charge. Or those that spend alot of time with the engine off and the stereo on. The need for maintaining the battery(s) charge just extends the life of the battery.

I have complained to the dealer on multiple occasions about this and have already replaced one battery. Dealer states system checks out with normal amount of key off draw.

Thrall
12-07-2010, 02:30 PM
I have complained to the dealer on multiple occasions about this and have already replaced one battery. Dealer states system checks out with normal amount of key off draw.

That's not right. Key off draw could only be to maintain time and presets on the stereo and clock on the dash I'd think. If it draws enough to kill the battery in a few weeks, maybe winter time is the right time to isolate the problem. Sucks I know especially since it should be warranty if you haven't added a bunch of electronic components to the boat yourself.
I'd try disconnecting certain loads and see of your battery maintains. Start with disconeccting audio amps, let it set a couple weeks, see what happens. Repeat with the main load wire going to the dash/guages and again with the lead to the engine components and if necessary with the lead going to the ballast pumps if you have ballast. One of those 4 is the culprit. Or you could get an amp meter and check each load, but I don't know what allowable limits are.

vision
12-07-2010, 04:32 PM
What type of battery? I had two Optima blue tops in my 08 when it arrived. Both were bad and would barely hold a charge new. Replaced with two Dekas and no problems in 3 years.

Possibly the dealer has a bad batch of batteries if they installed both? If you physically disconnect the battery, how long does it maintain a charge?

In my previous X2, we would accidentally kill a battery by leaving on ballast pumps or courtesy lights or the seat heater or the heater fan, etc. There are an amazing number of accessories that will remain on when the key is off. Malibu has a nice All Off button. I can see the utility of such a button.