Moving battery to trunk, any suggestions? - Page 3 - PeachParts Mercedes-Benz Forum

w123fanman · #31 04-29-2014, 10:07 PM

Quote:

Originally Posted by greazzer

Before the alarm bell is rang regarding the potential fire ball of death ... take a peek at some newer technology batteries. Relocation under the back seat, for example, involves NO lead acid batteries. They DO NOT fit. They are too big. EarthX, et cet., and the newer technlogy batteries are non-toxic, they don't ooze toxic fumes, or any other of the nasty stuff which LEAD ACID batteries do. Actually, they can be mounted or oriented in any direction, even upside down (some of them, but not all manufactureres).

In regards to a trunk mounted battery, there is ample room on the passenger side rear cargo "pocket" area (or the driver side too). There is NO need to lose your spare tire. No one mentioned this, but the spare tire in a W123 is actually part of the safety features for a rear end collision. The only confusion about a trunk mounted battery is a forum member who claimed and jumped up and down it won't fit. Well, a Group 49 Battery does in fact fit. I had a battery box oversized to permit dense foam all the way around. and it still fit perfectly in the cargo pocket area.

As for all of the anticipated problems, I discovered nor had any of them.

Battery Box Relocation

I had the battery in my trunk, neatly and nicely tucked away in a homemade battery box for well over an entire year. As for charging, no issues. I ran a bunch of electrical odds and ends for my WVO system and still kept the OEM 55 AMP altenator and never a charging problem, never a starting problem, et cet. My car got totaled and that ended that until I got a new MB. The only thing I would do different is the following:

1. Thicker cable, next size up
2. Make sure you try out some Anderson connectors
3. Get 20' feet of cable and don't sweat being short
3. Think about under the back seat. Very pricey compared to a lead battery, but it neatens up the area. I initially said no way, but I was 100% wrong on that. I had to search outside of traditional batteris. The folks at Odyssey, EarthX, and a few others really know batteries, their safety issues and considerations, et cet.

Does this mod HAVE to be done ? Of course not. It's not necessary at all. But, if you are doing mod's which require turf be cleared out, then it's an option.

I have decided not to bother with the battery relocation idea for now but may try a few things in the future. Once I looked them up I realized I have plenty of Anderson Connectors from winches, they really are nice to have. My idea instead of moving the main battery to the trunk is either one of the sealed batteries under the seat or in the trunk or maybe even a bank of capacitors under the rear seat (some people use them as a supplement to a battery). Sam's sells an AGM Group 49 battery for $167, might be the best bet for a battery in a sealed environment.

w123fanman · #32 04-30-2014, 11:17 PM

Got it welded up last night, the battery is staying in the front for now. Hoped the ground was what was causing other issues in the car like the tach, fuel gauge, and antenna, but nothing changed. I checked the antenna that had been working when we bought it, voltage is going to it and the housing is hot. The PO had the mast replaced a few months age but now it seems the motor isn't working.

compu_85 · #33 05-19-2014, 11:14 AM

New V6 Passats have the battery in the trunk. fWIW there is a huge fuse (1200 amp?) on the battery cable.

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TheDon · #34 05-19-2014, 12:15 PM

Quote:

Originally Posted by Benzkid_300D

It frees up a lot of room in the engine bay and helps weight distribution

(And batteries in the trunk are cool)

You're in the wrong car to consider weight distribution. Save your money for something more useful.

bricktron · #35 05-20-2014, 12:17 PM

noone else seems concerned with this, but the best reason to do this mod in my book, is to clean out the engine bay.