MightyMax 18Ah AGM battery

[sternwake]

SO this 18Ah AGm battery has not been used for jumpstarting, It has only been very lightly discharged when used as a portable 12v power source, mostly powering fans and then usually quickly returned to brimming full.

I acquired some free metric 8mm2 wiring, which is just a bit thinner gauge than 8AWG, which would correspon to 8.26 mm2 cross section. Today, I bought 4 8AWG Ancor heavy duty ring terminals with a #10 hole and 2 6AWG with 1/4 inch hole and used up the last of my 45 amp anderson powerpole( ANEN windcamp Anderson clones)

I have two short runs of this ( almost) 8 gauge wiring from this battery, through a pair of 45 amps powerpoles. These powerpoles and ~8awg paired wires will then goto the cables which are in my engine compartment where the starter battery would be, if I had a starter battery in this stock location. I stuffed two wires into one 6awg ring terminal and will just tighten these down in the post clamps that are currently wrapped up with electrical tape. All ring terminals crimped with hydraulic crimper. The early HF crimper dies are so far off, i used the ones labelled 4awg to do 8awg lugs, and then used another set of dies that I filed out previously to properly crimp the 8awg lugs into a nice hexagon.

With the powerpoles connected, I will be able to simply turn my Main battery switch from battery 2( Northstar AGM-27) to battery 1, and be able to start the engine solely on the 18Ah AGM battery, or BOTH to have the 18Ah battery assist the Northstar in starng the engin, and or powering house loads..

I am assuming the 18 AH MM battery will be able to start it. If not the Switch goes back to battery 2, or to the BOTH position.

The MM 18Ah AGm battery will reside under where the original battery tray once resided. Not sure how I wlll keep it in place, yet but there is a divider in place which used to support the original battery tray which I cut out in june 2015 and never bothered to replace.

I have a pair of alligator clamps to which I have previously attached 8awg leads. I think these clamps came with a schumacher sc2500a charger I bought in 2007. The 8AWG attaches to one side of the clamp and goes to 45 amp anserson powerpoles, and to the other side of the clamp, I just added the 8mm2 wire to another set of powerpoles. So the wiring between battery and my original post clamps, or these alligator clamps is basically safe to continuously carry 90 amps.

My starter is rated at 1400 watts, which is 140 amps at 10 volts, 155.5amps at 9 volts. I am fairly confident the anderson powerpoles should be able to handle this amount of amperage for short durations. Enough to test anyway, not as if I will regularly ask this battery or the two pairs od 45amp Andersons to pass starter current. I just want to see if it/they can.

Anyway I have two wattmeters rated at 130 amps each( briefly) that I can hook inline when starting the engine. These wattmeters can easily handle 40 amps continuous so I expect they will have no issue with 80 amps briefly.

I will be able to see how low the battery voltage falls when cranking the v8 engine with just this 18 AH AGM battery, the maximum amperage consumed, the maximum wattage consumed, and also AH and watt hours, and I will do so tomorrow.

I will also be able to see how much this battery provides to assist the Northstar -27AGm. at various states of charge.

In theory I could leave my battery switch to BOTH, as both have the same recommended charging voltages. The battery seems to rest fully charged( 13.18v) at a higher voltage than the Northstar( 13.06v) so the Northstar will always pull the mm AGm down to 13.06v wut hno charging source present, which is less than ideal, and they wilol both generally be the same voltage if discharged together.

Anyway, more data coming, soon.