Do EVs vary in how quickly they can charge?

Here’s our latest question from a reader:

Hi Bryce – thanks for your recent AEVA meeting presentation. Re your table re EV charging times – it confirmed my concerns about how EVs don’t seem to charge equally quickly at DC quick-chargers. Is the Kona particularly slow or do all EVs vary in their charging times and their maximum kW rating?

Kay Wennagel; presenter, BZE Science and solutions half-hour on Melbourne 3CR radio

Hi Kay – I’ll take the long way around to answering your question – there is a bit of history, as well as marketing spin involved that I feel the need to explain first.

To begin with, several years ago I wrote an article called ‘Plug Wars’. At the end of that article I said that when the Plug War finished (predicting that in Australia, Type 2 AC and CCS2 DC would be settled on – as has effectively happened) the next battle would start.

I called that new one ‘the charging speed advertising battle’. Your allusion to DC ‘concerns’ relates to that new battle front.

Each manufacturer is now involved in a hype war, saying their cars charge up incrementally faster than the others …. without actually hitting the maximum in one shot. That keeps their ‘powder dry’ to enable the battle to rage on for a couple more years until they all hit the top DC charge rate and move on.

For technical (and sensible speed) reasons, 350kW DC charging will likely become the upper limit – and one company is already about to announce their car does that. Others are already planning to follow, so one could say the DC charge rate battle is already half over.

(By the way, the maximum AC charging rate is pretty much settled at 7.2 or 11kW, as going over 11kW makes the AC to DC converter in the car rather expensive and bulky – which is why only Renault have gone there with 22kW and 40kW AC charging using their own integrated ‘Chamelion’ charger using the motor as part of the charger).

So where are we in this battle? The Porsche Taycan (along with Long Range Tesla models) can already charge at 250kW DC, and Porsche will soon announce the Taycan can charge at 350kW. Rivian will likely be the next to 350kW when they release in 2021 or 2022, then Ford with their Rivian-based models, etc, etc.

(NB: 350kW charging requires an 800V DC battery architecture and most EVs currently are 400V DC. This is why there will be a time lag in getting to the very highest charge rates).

By the way: the battle is not limited to the car manufacturers – the Ionity DC charging network has also started some rather fanciful electricity tariff rates based on a ‘theirs are the fastest’ mantra – Ionity 350kW chargers in the UK are ridiculously priced compared to their 50, 100 and 150kW competitors.

In summary, we are currently mid-cycle in DC charging rate announcements. Older EVs are 50kW, newer ones are gradually increasing to 70, 100, 150, 250 and eventually 350.

Regarding you comment about the Kona DC charging rate: well, in some ways the Kona has been around for a bit and could be seen as ‘old tech’ re DC, which is why it is still 70kW.

It is, however, rumoured that Hyundai is about to do a flanking manoeuvre and announce 11kW AC charging. (No announcements seem imminent from them on the main DC battle front though).

Mind you, I would say 70kW DC charging gives me highway stops no longer than those I would make in a petrol/diesel equivalent – above that just improves the EV driving experience over interstate trips in petrol/diesel vehicles, and I definitely don’t miss the oily patch on the fuel-station forecourt greasing up my shoes and the diesel smelling hands after using a diesel pump …

Summing up: being mid-cycle in the ‘charging speed advertising battle’ means we currently have a variation in DC charging rates, depending on what EV you buy.

Eventually, this will settle around 250 – 350kW for DC charging and the battle front for snaring consumer dollars will move on to create another point of difference between manufacturers. Chrome tail fins, anyone?