Looks right to me. Also, if we do end up seeing a terminal voltage of 450v rather than about 455v after the last update, I really don't think we need to be worrying.Nominal voltage on battery 394.2 divided by nominal voltage on cells 3.65 = 108
I'll stop posting now haha, anyone please feel free to correct me, but it does look as though these are the cells used in our cars.
108 in series? 4.21 v percell at 455v, a bit highThere 18 big batteries, so there must be 6 of these cells packed into each big battery.
I tried this today, charged and balanced up to 455v, drove until it went to 450v and got 6.5 miles.Looks right to me. Also, if we do end up seeing a terminal voltage of 450v rather than about 455v after the last update, I really don't think we need to be worrying.
They appear to have decided to drop the cell voltage from about 4.2v to 4.16\17v. This will be good for longevity of the battery. As for range, if you study a typical charge curve for this chemistry, the difference between 4.2v and 4.17v from a range point of view is measured more in yards than miles!
If anyone would like to prove it who is running the older BMS software with the finishing 455v or so. Please go and drive 1 mile. I'll be willing to bet before you've got to a mile, the voltage will be at 450v or lower.![]()
Thanks for the research. That's unexpected, there really shouldn't be anywhere near that much energy between 4.16v & 4.2v per cell!I tried this today, charged and balanced up to 455v, drove until it went to 450v and got 6.5 miles.
So about 5% of capacity. There shouldn't be that much energy with this chemistry between 4.16v & 4.2v per cell. I'm wondering how accurate the voltage reading is now...It did 3.3 miles per kw, it was only around town, so you could say it's about 2kw worth.
So have you had the latest BMS update?So about 5% of capacity. There shouldn't be that much energy with this chemistry between 4.16v & 4.2v per cell. I'm wondering how accurate the voltage reading is now...
I'm looking forward to doing a full discharge to see what range I'm actually getting now and how it compares to the reported miles per kWh so I can see what the useable capacity is.
Sounds very complicated.So about 5% of capacity. There shouldn't be that much energy with this chemistry between 4.16v & 4.2v per cell. I'm wondering how accurate the voltage reading is now...
I'm looking forward to doing a full discharge to see what range I'm actually getting now and how it compares to the reported miles per kWh so I can see what the useable capacity is.
I’m far from an expert on lithium-ion batteries , however my observations are that when showing 100% charged they can show this % for quite a while until it drops in normal use. For example my Apple iPad shows 100% after a charge - I can use it for quite a while - say 20mins and it will still show 100% before it eventually starts to drop. Is it not also that EV‘s produce more power when their batteries are fully charged than when say 25% charged? At the other end of charge (when low on charge) the battery seems to reduce at a greater rate. It’s the reverse of charging - faster from low charge, slowly reducing as the battery becomes quite full - to a trickle to finish off. I’m not sure what all this means but it’s interesting.So about 5% of capacity. There shouldn't be that much energy with this chemistry between 4.16v & 4.2v per cell. I'm wondering how accurate the voltage reading is now...
I'm looking forward to doing a full discharge to see what range I'm actually getting now and how it compares to the reported miles per kWh so I can see what the useable capacity is.
Let me see if I can find a discharge curve, it will help you see my point...I’m far from an expert on lithium-ion batteries , however my observations are that when showing 100% charged they can show this % for quite a while until it drops in normal use. For example my Apple iPad shows 100% after a charge - I can use it for quite a while - say 20mins and it will still show 100% before it eventually starts to drop. Is it not also that EV‘s produce more power when their batteries are fully charged than when say 25% charged? At the other end of charge (when low on charge) the battery seems to reduce at a greater rate. It’s the reverse of charging - faster from low charge, slowly reducing as the battery becomes quite full - to a trickle to finish off. I’m not sure what all this means but it’s interesting.
Had a BMS upgrade today as was told the last software update caused a bit of a problem - I have complained about the reduced range since the last update and today MG have offered to pay for my first service as a gift towards more charging that I have incurred !!!My AS when fully charged reads 450 volts does this number suggest my MY needs the latest BMS upgrade? I got the car in November.