I thought about using two units to measure in and out current. Or just a switch to reverse the polarity of the voltage from the shunt. But it would not provide the state of charge easily.
red31 wrote:
This $25 version goes both ways! 25A may not be enough!!!
http://www.ebay.com/itm/DC-120V-25A-Amp-Volt-Combo-Meter-Battery-Monitor-Capacity-Power-Charge-Discharge-/161120594598?pt=LH_DefaultDomain_0&hash=item2583892aa6
Thank you, Red! I think the 25 A would do. And that is probably as much as I want to pay for something with dubious accuracy. It is on ebay.ca at $35 plus $10 shipping.
I appreciate the reminder of the density measurement. I must get one of those.
The simple voltage measurement hours after any charging may be adequate after all.