Charging our EV is incredibly convenient. I can plug it into the socket in the garage whenever I want.
I plug it in overnight and it’s full in the morning, just like my phone. And to power our current driving habits I only have to do that once or twice a week.
I love that convenience because I no longer have to take time out to stop at a petrol station to fill up. There’s no more “tank anxiety”.
But something I’ve noticed, charging the final percent or two takes a disproportionate amount of time. I’d heard about this, and decided to test it for myself.
The graph shows a very linear progression until the last hour or two, when it really tails off. It was 99% and 30 mins remaining for over an hour. Does anyone know why this is?
I thought it might be slowing down deliberately, but the power consumption was a consistent 2 kW throughout, measured at the meter.
It means I’m not getting as much bang for my buck out of that last hour. Rather than adding 3% to the battery, like most of the charging, I’m adding less than 1%.
I also noted that while I was consuming a steady 2 kW at the meter, I was only adding 1.85 kWh/h to the battery. I assume this is just the energy lost when charging a battery, since the round trip efficiency is less than 100%?
I’d love to hear what other EV drivers have found, and any explanations for this. Let me know your thoughts below.
Note: Gavin Mooney is the Country Manager for powercloud in Australia, working with utilities to help them transform the way they run and embrace the energy transition. Â He recently bought a Model Y and has been writing about his experiences and learnings on LinkedIn. Reproduced with permission of the author.
See also:Â Instant torque and no noise: How an EV convert fell in love with his Model Y