An OCV 12.0V battery connected to another more charged battery OCV 12.6V
.6V / .01Ohm = 60A... Terminal voltage goes to 12.5xV and the batteries balance their charge, current tapers off as voltage difference tapers off?
OCV 14.6V alternator hooked to OCV 12V battery
2.6V / .01Ohm = 260A... If the alternator is really big say 400A then 260A flows and battery boils like crazy and maybe explodes? 60A alternator gets maxed out with say 20A going to electronics and lights and maybe 40A going to the battery? That's a fast battery charge, 100Ah starting batteries are designed to handle high .4/C rate and just be full all the time? Starting the engine make battery drop slightly on charge and then gets topped right off seconds or minutes after alternator is spinning and the alternator controller lowers the field pulse duty cycle to produce 13.6V float voltage?
Ohm's law is simple math, but me and I'm sure alot of other people don't realize the .01 Ohm typical resistance of a lead acid and the voltage difference between the charger and battery divided by the internal resistance = the potential amperage flow if the charger has enough current?
A year ago I was charging a lead acid starting battery for a Jeep with a spare 90W 19.5V laptop PSU (cause I didn't have a dedicated lead acid battery charger). I disconnected the vehicle clamp (to remove any vehicle drains from my unorthodox charging to make things simple) and I hooked up the PSU to the battery and the PSU was overheating like I thought it would, so I plugged the PSU into a Kill-a-Watt and saw it was taking 180W, then I used a piece of steel wire as a resistor between the battery and PSU to slow it down (and waste a few watts as heat) and adjusted the resistor till the PSU was taking in 100W. I left the PSU hooked up till the specific gravity stopped rising, I was able to turn down the resistance less and less and did not need the resistor towards the end, without overheating the PSU, 15V OCV battery lets say, 19.5V - 15V = 4.5V, 4.5V / .01Ohm = 450A, should have overloaded the 4.6A PSU right? This observation I had leaves me confused, unless the battery Ri was at least 1.022 Ohm? I swear I saw 15V terminal voltage with the PSU hooked up without the resistor. Or the PSU was unable to push more than it's 4.6A thru the battery for some reason once it was charged?
.6V / .01Ohm = 60A... Terminal voltage goes to 12.5xV and the batteries balance their charge, current tapers off as voltage difference tapers off?
OCV 14.6V alternator hooked to OCV 12V battery
2.6V / .01Ohm = 260A... If the alternator is really big say 400A then 260A flows and battery boils like crazy and maybe explodes? 60A alternator gets maxed out with say 20A going to electronics and lights and maybe 40A going to the battery? That's a fast battery charge, 100Ah starting batteries are designed to handle high .4/C rate and just be full all the time? Starting the engine make battery drop slightly on charge and then gets topped right off seconds or minutes after alternator is spinning and the alternator controller lowers the field pulse duty cycle to produce 13.6V float voltage?
Ohm's law is simple math, but me and I'm sure alot of other people don't realize the .01 Ohm typical resistance of a lead acid and the voltage difference between the charger and battery divided by the internal resistance = the potential amperage flow if the charger has enough current?
A year ago I was charging a lead acid starting battery for a Jeep with a spare 90W 19.5V laptop PSU (cause I didn't have a dedicated lead acid battery charger). I disconnected the vehicle clamp (to remove any vehicle drains from my unorthodox charging to make things simple) and I hooked up the PSU to the battery and the PSU was overheating like I thought it would, so I plugged the PSU into a Kill-a-Watt and saw it was taking 180W, then I used a piece of steel wire as a resistor between the battery and PSU to slow it down (and waste a few watts as heat) and adjusted the resistor till the PSU was taking in 100W. I left the PSU hooked up till the specific gravity stopped rising, I was able to turn down the resistance less and less and did not need the resistor towards the end, without overheating the PSU, 15V OCV battery lets say, 19.5V - 15V = 4.5V, 4.5V / .01Ohm = 450A, should have overloaded the 4.6A PSU right? This observation I had leaves me confused, unless the battery Ri was at least 1.022 Ohm? I swear I saw 15V terminal voltage with the PSU hooked up without the resistor. Or the PSU was unable to push more than it's 4.6A thru the battery for some reason once it was charged?
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