So during the last great pre-pandemic bail out in the USA I was downsized from General Motors Engineering Department Service Parts NAO. In just a few short days after leaving GM I had my own shiny new parts store I ran for 2 years before taking over a region for a while. Gone was the high blood pressure, the compulsive hand washing and ulcer almost over night. Everyday was like a vacation!
They had a 240 amp battery charger in back. It was fully automated enclosed and also tested as it charged. It was not a switcher either.
So other than the boiling point of the electrolyte and the temperature at which the plates will be destroyed what is the rate limiter to how much current the lead acid battery can accept in any give amount of time?
240 amps seemed like a bit much. This charger if it made it past 15 minutes for the full 45-60 minutes charge cycle the battery normally was fine and we never saw the customer again for a battery. If a battery was truly bad the machine would normally reveal that inside the first 15 minutes usually under 5 minutes. We would take a battery from that rapid charger and test it with another automated tester that was a fair bit more sophisticated than Midtronics unit that tested under some rather sophisticated loads completely automated.
On top of this back in the day when dinosaurs roamed the earth and large heavy steel and copper transformers ruled the earth battery chargers often had some pretty seriously high voltage above 12V. Todays little 4amp trickle chargers often have various pulse modes that will go up to at least 15V.
Many of the Toyota's I have owned especially in the 1980's and 1990's would float at 14.7-15.5 volts as a norm not a sign of a dish charged battery do to short trips and incomplete charge. Most of my GM cars would hit 14.5V cold but would quickly drop to 13.8. My mom owned a Plymouth Laser 1991/1992 that if you did not drive it enough to keep the battery nicely charged would run between 17v-19v trying to keep the battery charged and that ate batteries like crazy. She only drove it 2 miles to work and 2 miles home and when she got a company car it was even worse.
So what is the sweet spot for automotive 12V lead acid start/run batteries? What is the ragged edge? What is the limit before you start to damage them? How does one actual know real time what the health is of the battery?
As a young automotive technician prior to going off to college back in the 1980's in Germany we had to test the entire battery for voltage and current, specific gravity and we had to check voltage of each cell. Only if 2 or more cells where bad did we warranty the battery. Of course we had to have the proper water level and the battery had to be charged over night before the test's could be conducted.
I know this is a lot to ask about. That said I have never seen a good write up on these topics. When I come across anything it is written at a level on par with a what I would expect from a graduate student writing a technical paper and is so condition specific as to not be of much use to anyone not at that level. They are normally industry level white papers.
It would be great to have to a better understanding of the lead acid start/run battery it's best practices and what is realistic in it's care and feeding and rehabilitation for best possible life expectancy. Not a white paper aimed at Electrical Engineer's!
Thanks in advance! Not an Electrical Engineer! Long live J. C. Maxwell
They had a 240 amp battery charger in back. It was fully automated enclosed and also tested as it charged. It was not a switcher either.
So other than the boiling point of the electrolyte and the temperature at which the plates will be destroyed what is the rate limiter to how much current the lead acid battery can accept in any give amount of time?
240 amps seemed like a bit much. This charger if it made it past 15 minutes for the full 45-60 minutes charge cycle the battery normally was fine and we never saw the customer again for a battery. If a battery was truly bad the machine would normally reveal that inside the first 15 minutes usually under 5 minutes. We would take a battery from that rapid charger and test it with another automated tester that was a fair bit more sophisticated than Midtronics unit that tested under some rather sophisticated loads completely automated.
On top of this back in the day when dinosaurs roamed the earth and large heavy steel and copper transformers ruled the earth battery chargers often had some pretty seriously high voltage above 12V. Todays little 4amp trickle chargers often have various pulse modes that will go up to at least 15V.
Many of the Toyota's I have owned especially in the 1980's and 1990's would float at 14.7-15.5 volts as a norm not a sign of a dish charged battery do to short trips and incomplete charge. Most of my GM cars would hit 14.5V cold but would quickly drop to 13.8. My mom owned a Plymouth Laser 1991/1992 that if you did not drive it enough to keep the battery nicely charged would run between 17v-19v trying to keep the battery charged and that ate batteries like crazy. She only drove it 2 miles to work and 2 miles home and when she got a company car it was even worse.
So what is the sweet spot for automotive 12V lead acid start/run batteries? What is the ragged edge? What is the limit before you start to damage them? How does one actual know real time what the health is of the battery?
As a young automotive technician prior to going off to college back in the 1980's in Germany we had to test the entire battery for voltage and current, specific gravity and we had to check voltage of each cell. Only if 2 or more cells where bad did we warranty the battery. Of course we had to have the proper water level and the battery had to be charged over night before the test's could be conducted.
I know this is a lot to ask about. That said I have never seen a good write up on these topics. When I come across anything it is written at a level on par with a what I would expect from a graduate student writing a technical paper and is so condition specific as to not be of much use to anyone not at that level. They are normally industry level white papers.
It would be great to have to a better understanding of the lead acid start/run battery it's best practices and what is realistic in it's care and feeding and rehabilitation for best possible life expectancy. Not a white paper aimed at Electrical Engineer's!
Thanks in advance! Not an Electrical Engineer! Long live J. C. Maxwell
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