wrcsixeight
Adventurer
I am running both a Northstar AGM battery, and a Flooded group 31 USbattery. The Northstar is pretty similar to DHP/ Odyssey batteries in construction materials and charging requirements
I have many methods to see how much current either my solar or alternator or other charging sources are making, what states of charge generally either battery is in, and how much current is flowing to either battery.
Some UNexpected readings have occurred.
Like when my flooded battery is depleted and the AGM is full.
One might think the lower resistance AGM battery will suck up a majority of the current even though it is full and overcharge and fail.
My clamp on Ammeter showed that when the batteries were paralleled and the AGM was fully charged and allowed to feed on alternator current, the AGM battery was only requiring 0.2 amps to hold 14.7 while the depleted flooded battery was requiring 45 amps to be held at 14.7v. This to me disproves the AGM getting overcharged. 0.2 amps at 14.7v is not going to open the AGM's vents. When plugged in and charging for longer, this 0.2 amps will eventually drop down to current so low my meters will not read it, but the flooded battery will always take some current no matter how long it has been charging.
I do suspect that if both batteries were discharged the AGM battery would steal a majority of charging current if the batteries are in parallel while charging, but have not done an experiment to verify this theory. I am no longer of the opinion that one cannot safely charge an AGM and a flooded battery in parallel safely, as long as the voltage does not exceed either batteries maximum allotted voltage.
What I do not want to do is leave the batteries in parallel with no charging current available. My Northstar AGM has a fully charged resting voltage of nearly 13.1v, my Flooded USbattery's fully charged resting voltage is 12.8v and would always feed from the 13.1v Northstar until both batteries were at equal voltage.
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Copper clad aluminum wire needs to be thicker for the same voltage drop at the same amperage as pure copper. It is lighter and less expensive and fine, as long as it is thicker to compensate for its higher resistance. I don;t know how much better CCA would be compared to pure aluminum. Do be suspicious of any seller who is selling thick cabling for significantly less money. My friend just returned many feet of 0/1 gauge aluminum wire, even after contacting the seller and confirming it indeed was pure copper. Some are also selling Aluminum wire as tinned copper wire, as the appearance, not weight, are similar. Tinned copper wire is popular in the marine world.
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