Dual Battery Setup???

I'm looking to run a dual battery setup and I'm trying to find a battery isolator to use in the setup. Any suggestions would be greatly appreciated.

Thanks.

marine battery switch

http://www.iboatsimages.com/mall/image/view/3/9/8502_0.jpg

I was thinking more like this.....It allows both batteries to be charged, but the accessory battery cannot drain the vehicle battery, so you should never be stranded.

Was wondering if HerrHelmet from

http://advrider.com/forums/showthread.php?t=629665

might have good info?...shall pm him this thread.
Great question...being stuck without sufficient battery power is creepy...love to hear input....

yatman

I think both of the above ideas would work. I was a sailor long before I got into the Lithium off-road battery biz, so I understand the need for battery isolation. Because of the high-amperage of the starting batteries, you will find that the Perko switch is pretty huge and heavy. (Had one on my boat) The heat sinked Isolator may be the better choice depending on how big and heavy it is.

I'm not aware of any Powersport deep cycle batteries but it leads to an interesting thought. If you combine a LiFEPO4 starting battery (HIgh pulse cranking amps) with a deep cycle (more amp hours) you would be able to run electronics, cell phones, gps etc. while camping) In either case a perfect opportunity to go to lighter batteries.

One bit of news concerning the LiFEPO4 is that we will be offering a complete battery management system built in a sealed watertight case with center mounted terminals for universal fit. This system eliminates the need for a balance charger, or any kind of charger for that matter. Should be available in about 2 weeks.

HH

Great thread.
Thanks

HH,

I agree with you that the marine type switch is a little bulky and doesn't give me the function I'm looking for. The heat sink isolator is what I would like to go with, but like you mentioned they are designed for use in cars and trucks and a little large, but I'm running a tour pack. My hope was there might be one designed for motorcycles and that's why I asked here figuring the adventure world would be the place to find it.

If your company designs a deep cycle battery let me know.

I started looking for an isolator for motorcycles a couple of years ago, but nothing specifically designed. When I ride long distance though remote terrain, I always bring a spare battery. I use quick disconnects and you could set up your batteries with those, but you would have to manually switch them. If the batteries are accessed easily under the seat, it's the lightest solution, not the most sano.

We will have a deep cycle battery soon too!

This set up looks doable and the right size for application. http://www.dfna.info/smart-battery-isolator.html

Most any auto parts store should be able to fix you up with a basic relay switch. With a relay switch when you turn the key on and start the bike the switch closes and connects the second battery to the bikes system. When you turn the bike off the switch opens isolating the second battery. Maybe also called a continuous duty solenoid.

That looks like something that might work. Never thought about the atv world especially since the side-by sides came out. Thanks for the link, I'll do a little research on it and see if it will do what I want.

I did a bunch of reading on the AOPEC Smart Battery Isolator and it looks like a good choice, but there is one thing I'm having a hard time verifying. Does anyone know if it has diodes on each of the battery legs to truly isolate the batteries from each other or is it just a relay?

Thanks.

I can't be 100% certain, but it looks like it uses a relay contact. It looks to have electronics to sense when there is a high voltage, that is, the charger is charging, then it fires a relay.

I've thought this over a number of times is I tow a small camper with a 12 volt battery in it. Diodes alone aren't a good idea. They keep the voltage at the battery too low to get a really good charge. I now have a schottky diode in line with the battery in my camper. The schottky diode has maybe a 0.3 volt drop. The system wiring adds a few more tenths of a volt. My motorcycle battery is around 14.2 volts. The camper battery probably never sees much more then 13.5 volts and the battery just never gets a good top off. I actually need a system to boost the voltage a little for a good charge on the camper battery. A relay would work better in my case.

I got a response from AOPEC and it is a relay system. I'm going to have to figure out what my stator output is in amps and I'll figure out which heat sink isolator will work for my application. Then I'm going to have to find a spot to install it on the bike. Maybe under the tour pack.

Once I start the install I'll get some progress pics up to show my setup.

Are you saying that you don't want a good relay system for some reason?

Why are you dibolically oppossed to an automatic charge relay type system ? :huh
On a motorcycle power is EXTREEMELY limited and the ACR has way more power loss then a diode type.

I don't like the relay systems, because they only isolate the power when the bike is turned off. When you look at the heat sink isolators they are true isolators and the two batteries can never affect each other no matter the state of the motorcycle. These can also protect the stator and rectifier-regulator from any issues from the batteries or anything I may attach to the bike.

Just my thoughts.

Well....am I missing something?

I'm just trying to get the best solution and so far based off of what I read and people I talked to the ACR didn't seem to fit all my wants, but I've been wrong before.

Sorry its 25 years of building ambulances and seeing all that can go wrong with diode type isolators
Number one concern is voltage loss and in ability for the charging system to sence both batteries ( or "turn on" the regulator if useing a non self exciting charge system )
I could go on ranting but

is there a specific reason your looking for dual batteries ?