Balanced Charging X's 4 6V Batteries

Balanced wiring - see the diagram in 2oldman post (also British article, it's a classic).

Balanced wiring is important not only for "charging" but for "discharging" as well. More important at high amps, less - at low amps.

The bottom-line is, when it's not more difficult to wire balanced, there is no reason to wire un-balanced :)

Use excellent soldered cables then measure to the millvolt voltage at the LEAD POST of each battery at point of MAXIMUM INTENSITY highest amperes of charge. This way there is no guesswork, no asssssssssssumptions.

It can make more of a difference than you might think.

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

Most folks only worry about it if they will be using high amps wrt bank AH capacity. Low amps give more time for the batteries to adjust among themselves.

Maybe I don't understand the question, but if I do, don't worry about it. The minor differences you'll experience in charging won't make hardly any difference while discharging over the long life of the batteries. Seven to 14 years if you do maintenance regularly.

You're only talking about a +/- 0.1 volt difference in readings from one battery to another anyway and that's within the tolerance of the meter. (Typically given as +/- 1 least significant digit). If your meter is typical, and you've set it on the 20 Volt scale, readings of 12.4 to 12.6 are reasonable where a precision meter would read 12.5. Noise makes a difference in readings too so if you want an accurate battery voltage measurement, you'll want the charger to be off, wait an hour for the surface charge to dissipate from the phantom loads most RVs have, and than disconnect all the batteries before measuring. Not much fun, not very practical, so most people shrug and don't bother with it.

And of course, there's the practical aspect of balanced charging. It's a method more suited to many cells in series and is usually used with Lithium batteries, not a series/parallel wet cell setup. So though Iota does a good job with their diagrams, they never really mention that, or mention that it's probably not possible to have perfect balance.

Is it practical (or even possible) to get your setup wired in such a way as to have perfect balance on every cell in every 6V battery? I doubt it. Maybe in the short term, but a month or three down the road, differences will creep in.