common power or ground between batteries?

[ncc74656]

i realize there is quite a bit of electrical theory going on here and it may not translate into real world benefit. however from an "on paper" standpoint: would one benefit from having all positive and negative posts of a 3 battery setup meet at one location before going out to devices? so for example: 2 batteries in front and one battery in the rear, all 3 batteries having a 5.5 foot length of power and ground wire coming from their respective terminals and into a copper distribution block. the alternator and starter both going into the power block at this location and the grounds for the frame/block/body all emanating from the grounding block.

in theory this would provide a fully balanced battery bank where each battery gets charged and discharged evenly correct?

[TRON]

"Fully balance battery bank"? Your equipment draws power from the batteries...connect batteries to equipment, done.

I don't really understand what you're trying to achieve.

[ncc74656]

current theory says that if you link batteries together in sub optimal ways you can be drawing up to a 20% difference in amperage from one battery to another, causing one battery to fail before the other.

i am trying to accomplish the most optimal power scenario for my amps, starter, electronics.

refrence: http://www.smartgauge.co.uk/batt_con.html

[rockFord_Expedition]

The shorter and thicker your runs of wire, the better off your electrical is. So if in your theory you are adding more wire than necessary to have everything meet at a dedicated hub then you aren't helping yourself any.

[_paralyzed_]

As long as you have adequate wire from battery to battery or battery to device it doesn't really matter. Adequate wire means being able to pass the maximum amount of current the entire system will pull. (Or produce, if charging)

[ncc74656]

thats a fair point. what is the math behind the MECP ground rule? (no longer than 18" and must go to body or frame). in terms of is it ever acceptable to run power and ground back up front to the battery?

while charging i suppose the battery draw order is a moot point isnt it? its not the batteries that are delivering most of the power but rather the alternator so the location of said batteries would be irrelevant so long as conductivity was not effected. right?

stereo concerns aside, i do want to ensure my starter gets optimal power. perhaps running a 0/2 run from each battery to the starter would ensure this? over kill perhaps but this engine is a pig in the cold.

if i have each battery grounded to the body/frame/block independent of the rest and the block grounded to the frame which is bolted to teh body... ground is going ot find its own path of least resistance... so its not going to matter from a conductivity stand point to each battery. lets say that a 800A draw is occurring and the best/first path to ground is into battery #2, while ground is also occurring to battery #1 and 3 is it possible for the circuit to not receive as much power as it needs due to a dominance occurring in the preferred grounding path in relation to the 3 batteries?

[rockFord_Expedition]

Batteries aren't delivering any juice until voltage drops low enough for them to contribute. Making sure you have a solid return path to the alternator is paramount.

In almost every application, front to back ground runs although sometimes adequate, are only beneficial if you have enough wire to allow more current flow than the frame of the vehicle, and there aren't too many of those. They can also help eliminate alternator whine in some cases.

[OrionStang]

OP is way overthinking things. As long as all positives (alts and batts) are connected cleanly, and grounds are sufficient, there should be nothing to worry about.