MG5 long range 71 plate SOH After 62000 miles. Do you have any figures?

I am told it might take a further 2 months for the repair.
That’s probably the time it takes for a replacement pack to be shipped.

Complete pack replacements are usually straightforward and done for other EVs in a couple of hours.
 
I am a little suspect over how the bms calculates soh
My soh has been dropping in a very very linear fashion alarmist exactly 0.01 percent per day

Apparently it has lost around 5 percent over its life so far in 19000 miles and three years. So about 3kwh

When I have charged from a very low level (about 4 percent) the amount of measured delivered power is pretty spot on to be full at 57kwh and a bit delivered

So either car scanner is reporting a loss from the total capacity or the bms calculations are simply wrong.

My gom now shows 239 fully charged in normal reset, but the full capacity appears to be spot on for 57kwh and change
And my range doing similar drives hasn’t dropped (within less than 0.5 percent)

Sigh ev’s do play into my ocd obsession gene :)
 
ICE vehicles lose both range and power, at least we keep the latter, but nobody makes a fuss about ICE degradation.

It's almost as if the fossil fuel industry are spreading FUD!
 
True but it’s much more difficult to measure without a dyno

I can obsess over this with tea at home :)
 
I am a little suspect over how the bms calculates soh
My soh has been dropping in a very very linear fashion alarmist exactly 0.01 percent per day

Apparently it has lost around 5 percent over its life so far in 19000 miles and three years. So about 3kwh

When I have charged from a very low level (about 4 percent) the amount of measured delivered power is pretty spot on to be full at 57kwh and a bit delivered

So either car scanner is reporting a loss from the total capacity or the bms calculations are simply wrong.

My gom now shows 239 fully charged in normal reset, but the full capacity appears to be spot on for 57kwh and change
And my range doing similar drives hasn’t dropped (within less than 0.5 percent)

Sigh ev’s do play into my ocd obsession gene :)
Your SoH doesn’t start @100%, it’s a couple of points higher to mask initial, rapid degradation.

Not all the power measured at the wall box goes actually into the battery only roughly 90% of it..
 
Yeah I am assuming 90 percent of total delivered and am working on 57.4 kWh out of the 61.1

I would also be surprised if the bms didn’t always hold 3percent at the top and bottom of the battery. So degradation is always the usable portion
Can’t find a definite answer on this though
 
I am a little suspect over how the bms calculates soh
My soh has been dropping in a very very linear fashion alarmist exactly 0.01 percent per day

Apparently it has lost around 5 percent over its life so far in 19000 miles and three years. So about 3kwh

When I have charged from a very low level (about 4 percent) the amount of measured delivered power is pretty spot on to be full at 57kwh and a bit delivered

So either car scanner is reporting a loss from the total capacity or the bms calculations are simply wrong.

My gom now shows 239 fully charged in normal reset, but the full capacity appears to be spot on for 57kwh and change
And my range doing similar drives hasn’t dropped (within less than 0.5 percent)

Sigh ev’s do play into my ocd obsession gene :)
Watch this video. It should make you feel much better - it did me!
 
I would also be surprised if the bms didn’t always hold 3percent at the top and bottom of the battery. So degradation is always the usable portion
Can’t find a definite answer on this though
The BMS prevents access the top/bottom ‘buffer’ therefore yes, degradation is always applied to the ‘usable’ portion.

How much energy did your wall station use for the 4%-100% charge, what speed are you AC charging at?
 
Started at 10 percent (my bad)
Charging at 6.77 ish kw
Drawing 7.03 ish (at peak charge)
Used total 53kwh
Delivered 51.7 ish
I assumed the car used a further 200w an hour to run it systems, so over 8 hours approx 1.6kw used by the car
50kwh approx delivered to the battery

I guess if the bms is always holding 6percent (which it must do) then the concept that degradation is hidden in the unusable portion of the battery can’t be true?
 
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I guess if the bms is always holding 6percent (which it must do) then the concept that degradation is hidden in the unusable portion of the battery can’t be true?

Let’s assume a single NMC cell has a voltage range of 2.5 to 4.3V but in order to improve longevity, the BMS limits the range from 3.0 to 4.1V. The charge/discharge curve isn’t linear, therefore you won’t loose much capacity by cutting off the top and bottom buffers.

What’s left is usable capacity and one would expect this value to be 57.4 kWh (for LR) @100% SoH, except it isn’t.

The battery is more likely manufactured to be around 60kWh (105% SoH) but starts losing capacity from day one, but as long as it remains above 100%, indicated SoH will not budge.

Only when degradation goes above 5% will you notice, therefore to answer your question: initial, rapid degradation is happening in the usable portion, but is deliberately hidden from you.
 
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