Can you charge a battery of higher voltage with a lower source voltage? Reason why I ask is that I notice when an alt charges a standard 12v it can be as high as 15V or as low as 13V but the voltage always comes out the same, 12.6V. Now if you charge say a 16V battery with a 15V alt voltage will that battery only reach 15V or woult the voltage accumalate and reach the batteries max? I asked the battery maker but they said it needs a 19.2V charge voltage and wanted to sell me a new alt, me thinks they are stupid and want to sell me extra sh!t.. Polo.
You can't charge a 16 volt battery with a 15 volt power source. Well, I guess you could, but it would only charge to 15 volts.
Notice with your example with the 12 volt battery, that charging voltage (13-15) is always higher than the battery (12). The battery will "draw" however much current it needs from the higher voltage source, but current will never flow from a lower voltage device to a higher voltage one. If you connected a 15 volt power source to an discharged 16 volt battery, it would charge to 15 volts, the voltage of the souce.
I understand what you are saying but I have heard of batteries acting like capacitors and as long as the plate voltage is achieved it would accumalate. A battery is made up of several plates each having there own voltage and as long as the minimum plate voltage, say 2.1V is reached the overal voltage would be accumalative. Now if what you say is true, then I should be able to run a 16V battery and charge it with a 16V output on the alt and still have a 16V accumalated battery voltage. According to the manufacture this won't happen, trying to figure out why.. Polo.
If the charging voltage were just a little higher than the battery's float voltage, say 16.001 volt charger on an exactly 16.0 volt battery, it would take a very long time for the battery to charge to 16.0. It can be said that volts are what "pushes" amperes, and it that case they are not pushing fast enough. (bad analogy but I can't come up with a better one)
Now I don't know exactly how much difference in voltage is necessary to charge a particular battery "quickly", or how to calculate that, but someone set the standard at 14 for 12 volt batteries.
