Subaru Dual Battery Setups

calicamper

Expedition Leader
Bummer but not really surprising with the XT its not an engine you can ignore or go long on ol changes. I run two group 31's in my 28ft 8000lb sailboat. Even one group 31 in the OB would be silly, for sure would not want it in the cabin during an accident.

Seems that an 80watt panel and a 75-80ah battery would support most 2-3 amp draw fridges in reasonable solar conditions. This seems far more logcal than two goup31s in a OB.
 

DanCooper

Adventurer
Midlife Crisis has a dual battery set up in his build in this forum, 2015-Subaru-Outback-Expedition-Retrofit starting at Post 36.
 

DanCooper

Adventurer
You are right, Grant, Mid-Life opted for no back seat in his build. But he does have a battery in the cabin, used in conjunction with a refrigerator. I didn't offer up the reference for an exact solution of battery and fridge placement, but just to show the OP that another Subaru owner has addressed a similar (not exact, but similar) problem in his own, unique, fitted solely to him, way.

I should have been more helpful, and pointed out that he, the OP, has roughly 41 inches of room between the rear seats and the tailgate. If, like you (and I'm not saying he should copy you, just that you solved your access to the fridge problem by putting it on a slider), he decides to put his fridge on a slider, he has some room for an appropriately sized battery on the slider with the fridge, or in a fixed position behind it (The Engel MT17 referenced by the OP dimensions are 21.2 x 14.2 x 12 inches). Or there is some room between the inner rear wheel fender and the tailgate.

I should have pointed out that the use of AGM batteries increases versatility, because they don't need to be positioned on their bottoms.

I should have pointed out that there is an excellent forum devoted to similar issues (not precisely the same issue, but similar) in the sub-forum here on Expedition Portal titled "Power Systems: 12v, Solar, Gen" over in the Expedition Support Equipment and Adventure Activities forum.

My bad. I'll try to do better.
 
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freshlikesushi

Free Candy
Correct. Though if you wish to USE said room, then a battery doesnt belong there


best case, behind a seat is a good option if you dont carry many passengers.

My personal way to do it (which i will be executing this winteR) Is to replace the main battery with a good AGM. Then run a second race batter (from like braille or the likes) and put it under the passenger seat. This will be your actual starting battery. its small footprint means you can put it almost anywhere, but its only good for a starting battery. This way you can run your main battery down, then use the race battery to start only
 

Detslider

Adventurer
Most of the discussion on here about adding a second battery focus on hard wiring it into the vehicle since the battery will be used to power items like a winch or aux lights which are affixed to the vehicle. Since you only want to power a fridge, which can be removed, I think a stand alone battery is the right idea.

Maybe a small, stand-alone AGM in the back would get the job done, or perhaps replacing the main battery with an AGM might get enough amp hours to make it work.
I use a Goal Zero Extreme 350 in the back of my Subaru to power a TruckFridge TF51/ IndelB TB51 which has the same exterior dimensions as your Engel so I'll assume they draw similar power. The GZ350 has a 350Wh, 33Ah battery which will power my fridge for anything between 1-4 days depending on ambient temperature and how full it is inside. Yes, the GZ350 is small on power but it's also a small footprint which, as you've noted, is an important consideration in a Subaru. I connect it to a 12v outlet in the back hatch so when the vehicle is running it's recharging the battery and when I turn off the vehicle the 12v goes cold to prevent any drain on the starter battery.

What I really like about this setup is that it allows me to easily remove the fridge and battery between trips or if my cooking area is going to be some distance from the vehicle. This option also allows you to use your battery in situations unrelated to travel. I've used my GZ350 to power a speaker system at a movie theatre drive-in since the speakers on the poles sucked. I've used the GZ350 to power a work light out in a field where there was no power and running an extension cord was impractical. I keep it charging in the garage in case the house looses power I can charge phones and light a few rooms with a string of the GZ Light-a-life LED lamps.

Keep it simple.

http://www.expeditionportal.com/forum/forums/48-Power-Systems-12v-Solar-Gen
 

freshlikesushi

Free Candy
wait

so you are telling me this...

you would rather spend four hundred and fifty dollars on a yeti, than 2/3 of that on a battery...

get a bluetooth speaker with an aux jack in it, rechargeable lanterns, all stuff that you should have instead of a four hundred and fifty dollar battery

http://amzn.to/1GEdvOH

Im sure for you it sounds like a great idea, but it seems like alot of making a reason to have a toy. though to be fair. if i had that much to throw on a portable battery, i would also.
 
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Stroverlander

Adventurer
Correct. Though if you wish to USE said room, then a battery doesnt belong there


best case, behind a seat is a good option if you dont carry many passengers.

My personal way to do it (which i will be executing this winteR) Is to replace the main battery with a good AGM. Then run a second race batter (from like braille or the likes) and put it under the passenger seat. This will be your actual starting battery. its small footprint means you can put it almost anywhere, but its only good for a starting battery. This way you can run your main battery down, then use the race battery to start only
If you're planning on using a lithium-ion type battery, cold/freezing temps can be an issue for a starting battery not to mention using a charger that has a desulfation mode that can't be disabled. They are great to save weight on track/race motorcycles but in my experience, I'm not sure I'd want to rely on one to start my four wheel vehicle in everyday conditions. You may be better off with a jumper pack.

Is solar an option?

Not sure what size battery other Subaru's use but replaced the stock 35 in 2010 Impreza OBS with a 24F Bosch Platinum AGM (Exide Edge). Same terminal configuration, slightly better specs for same price, approximately 1" wider and fit with minor trimming to plastic battery tray. While there are probably better AGM battery options it was too good of a deal to pass up at Pep Boys - 30% off and $20 rebate.

There is room to go with an even bigger (wider) battery if you want to get closer to the valve cover, but additional depth may be an issue with stock mounting hardware.





 
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freshlikesushi

Free Candy
If you're planning on using a lithium-ion type battery, cold/freezing temps can be an issue for a starting battery not to mention using a charger that has a desulfation mode that can't be disabled. They are great to save weight on track/race motorcycles but in my experience, I'm not sure I'd want to rely on one to start my four wheel vehicle in everyday conditions. You may be better off with a jumper pack.
Since it will be interfaced with the stock charging situation, its not a huge deal. ILl be in florida starting next year, so cold isn't an issue.

I used a braille battery in my V8 miata for a few years with no issues, so im pretty happy with them
 

Detslider

Adventurer
Here you go: http://www.electriccarpartscompany.com/FBC-br-100Ah-3C-32V-br-LiFePo4-Lithium-Prismatic-EV-Battery-br-60-275-825-in-150-69-207-mm-br-772-Lb-35-Kg_p_41.html

Put 4 of those in series for a 100Ah 12v(+) pack that weighs 30lbs and can fit in small spaces or be configured how you need to (for example flat under a seat). Cost will be about $450 but you get as much capacity as a group 31 with longer life and a 40lb weight savings.
except 400 AH is pretty ****ty
100Ah is what a decent AGM 31 battery is rated at.

It will be a 100Ah pack not a 400Ah
if you say so :)
Four of these in series will make the voltage = 4x3.2V = 12.8V (will actually be a bit higher just like a lead acid) while maintaining the capacity of the individual cell or 100Ah
Weight for 4 = 7.72*4 = 30.88lbs or 45lbs lighter than the group 31 AGM.

Am I missing something?
McGee: I think the only thing you may have missed is Grant's internet wide self-proclamation that he's the expert in anything associated with “overlanding” (aka camping) and Subaru. Consequently, his build is the gold standard, his ideas are patent worthy and his word is not to be questioned…

Dan got the memo.

You are right, Grant

My bad. I'll try to do better.
 

Detslider

Adventurer
you would rather spend four hundred and fifty dollars on a yeti, than 2/3 of that on a battery...
Really? I only recommended the OP go with a stand alone, rather than hardwired, battery. I've had good luck with the GZ350 but there are other stand alone options.
Still, if you can put together a better package for $300 please post a shopping list.

Your first post in this thread was a recommendation for a $350 battery.
Your own plan seems to involve a $200 Braille battery, at least $75 in cables, relays, fuses, etc. plus the chore of installation. You'll probably need to buy a new battery tray for the Braille, maybe one for the battery under the hood if you're upgrading it as well. Add another $100 for a comparable inverter and you're probably pretty close to the cost of a Yeti 400.
Sure, the Yeti has about half the power of a full size battery but, as I said, I've been able to run my fridge for several days on a 33ah battery. The sacrifice of reduced power is offset by the ease of installation (none) and the ability to use the power pack in different ways, to include moving it to a different vehicle (a feature that is/was relevant to the OP who wants to have multiple vehicles in his fleet).

Im sure for you it sounds like a great idea, but it seems like alot of making a reason to have a toy. though to be fair. if i had that much to throw on a portable battery, i would also.
Admittedly, I initially only went this route because I got a deal on a used GZ350 but in the past three years I have well over 100 travel days/nights on this setup without issue and many more days of non-travel related use so.... yes, it was a great idea.

Edit to add: the Goal Zero Extreme 350 is discontinued but still available for $350 from some online retailers. http://www.jmsonline.net/goal-0-extreme-350i-kit-goa-39003.htm?utm_source=google_shopping&gclid=CLaBv-uU8MgCFcQRHwodVQQAkA
 
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Stroverlander

Adventurer
Since it will be interfaced with the stock charging situation, its not a huge deal. ILl be in florida starting next year, so cold isn't an issue.

I used a braille battery in my V8 miata for a few years with no issues, so im pretty happy with them

Was it AGM or lithium ion?

It does become sort of a big deal if it doesn't start your vehicle which I'm applying to the OP who lives in SW MI and not you specifically.
 

freshlikesushi

Free Candy
Really? I only recommended the OP go with a stand alone, rather than hardwired, battery. I've had good luck with the GZ350 but there are other stand alone options.
Still, if you can put together a better package for $300 please post a shopping list.

Your first post in this thread was a recommendation for a $350 battery.
Your own plan seems to involve a $200 Braille battery, at least $75 in cables, relays, fuses, etc. plus the chore of installation. You'll probably need to buy a new battery tray for the Braille, maybe one for the battery under the hood if you're upgrading it as well. Add another $100 for a comparable inverter and you're probably pretty close to the cost of a Yeti 400.
Sure, the Yeti has about half the power of a full size battery but, as I said, I've been able to run my fridge for several days on a 33ah battery. The sacrifice of reduced power is offset by the ease of installation (none) and the ability to use the power pack in different ways, to include moving it to a different vehicle (a feature that is/was relevant to the OP who wants to have multiple vehicles in his fleet).



Admittedly, I initially only went this route because I got a deal on a used GZ350 but in the past three years I have well over 100 travel days/nights on this setup without issue and many more days of non-travel related use so.... yes, it was a great idea.

Edit to add: the Goal Zero Extreme 350 is discontinued but still available for $350 from some online retailers. http://www.jmsonline.net/goal-0-extreme-350i-kit-goa-39003.htm?utm_source=google_shopping&gclid=CLaBv-uU8MgCFcQRHwodVQQAkA
to be fair. I recommended a single battery upgrade for HIM. I have different requirements, hence why i want a dual battery setup.
 

Stroverlander

Adventurer
Since you mentioned over-priced battery options...

Is that Braille still just a re-badged Deka AGM with adapter posts, fancy claims and twice the price for the same motorcycle battery?

You could pay half that for the Deka equivalent or similar size/spec Yuasa AGM like the GYZ20H / GYZ32HL / etc which would be my preference over Deka. Save some coin.
 
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