I'm a VCDS virgin but I have looked at the existing "battery coding" threads and none of them really hit the mark.
About to replace a 2014 Q5 battery, so it is the more recent battery management system, and I have experience with 12-volt charging systems. Enough to know that traditional automotive systems (plain alternator/regulator) are as one engineer put it "designed to not overcharge a battery" leaving it chronically but slightly undercharged. And the new computer BMS systems...lord only knows what each one does, no one will speak past "trade secret".
But in theory, a modern BMS is programmed for specific battery VOLTAGE, which may be 12.6 to 12.8, and that's a 20% difference in the battery being charged or not. With AGM batteries (mine is) this is pretty important for long battery life, the charging voltage must match the voltage of that particular maker, not just some average number.
Yes, the BMS needs to know the amperage capacity, that's apparent. But unlike a real BMS system, it does not provide for "optimum charging voltage" it only asks for the maker. Every maker has their own chemistry and their own voltage recommendations, so my first thought was "Is the "manufacturer" setting really pulling in a voltage setting?" but this gets more complicated, i.e. since companies like Varta (Germany) license their US operations to companies like JCI, who aren't necessarily using the same chemistry and voltage.
(And yes, I'm waiting for a callback from JCI.)
So is there any reference to just what the BMS changes when you select a different manufacturer? Is it just offering different amperage capacities, with no provision for setting the correct charge voltage? (The actual bulk charge can be somewhat loosely set, but for an AGM the best life comes when charging is stopped rather precisely, and the battery kept to a 100% charge, not just the 90-95% that a wet lead battery might be happy with.)
Any real technical information out there? I can't seem to find a hint of it. In deep cycle, solar, backup power, all the major battery applications, this is old hat and published. But Audi....ah, not quite.
About to replace a 2014 Q5 battery, so it is the more recent battery management system, and I have experience with 12-volt charging systems. Enough to know that traditional automotive systems (plain alternator/regulator) are as one engineer put it "designed to not overcharge a battery" leaving it chronically but slightly undercharged. And the new computer BMS systems...lord only knows what each one does, no one will speak past "trade secret".
But in theory, a modern BMS is programmed for specific battery VOLTAGE, which may be 12.6 to 12.8, and that's a 20% difference in the battery being charged or not. With AGM batteries (mine is) this is pretty important for long battery life, the charging voltage must match the voltage of that particular maker, not just some average number.
Yes, the BMS needs to know the amperage capacity, that's apparent. But unlike a real BMS system, it does not provide for "optimum charging voltage" it only asks for the maker. Every maker has their own chemistry and their own voltage recommendations, so my first thought was "Is the "manufacturer" setting really pulling in a voltage setting?" but this gets more complicated, i.e. since companies like Varta (Germany) license their US operations to companies like JCI, who aren't necessarily using the same chemistry and voltage.
(And yes, I'm waiting for a callback from JCI.)
So is there any reference to just what the BMS changes when you select a different manufacturer? Is it just offering different amperage capacities, with no provision for setting the correct charge voltage? (The actual bulk charge can be somewhat loosely set, but for an AGM the best life comes when charging is stopped rather precisely, and the battery kept to a 100% charge, not just the 90-95% that a wet lead battery might be happy with.)
Any real technical information out there? I can't seem to find a hint of it. In deep cycle, solar, backup power, all the major battery applications, this is old hat and published. But Audi....ah, not quite.