DC fast-charging performance varies depending on many factors, including a charger’s type. In today’s episode of State Of Charge, we will take a look at the 2024 Chevrolet Equinox EV 2RS FWD DC fast-charging test results at three different chargers — Electrify America (150 kW), Tesla Supercharger (250 kW), and EVgo (350 kW).

The new set of charging tests from 10% to 80% state-of-charge (SOC) reveals what to expect at different charger types and the importance of the battery’s voltage.

We already know that the Chevrolet Equinox EV is not the best DC fast-charging electric car on the market, but it’s an interesting city car. It has a relatively high EPA Combined range of up to 319 miles and an attractive price starting at an MSRP of $33,600 (+$1,395 DST). Including the $7,500 federal tax credit, its effective minimum cost is $27,495.

Specs

The front-wheel drive 2024 Chevrolet Equinox EV has an EPA Combined range of 319 miles. Its battery pack is believed to have a usable capacity of roughly 85 kilowatt-hours, consisting of ten Ultium battery modules of about 8.5 kWh each.

According to the manufacturer, the car can DC fast charge at up to 150 kilowatts peak, while its best range replenishment rate is up to 70 miles of driving range in 10 minutes. This means that even at peak charging power, the car’s battery will remain well under a 2C charging rate, which is significantly behind that of other top EVs.

The key specification of the Chevrolet Equinox EV’s battery is its nominal voltage of 288 volts. At a low SOC, it’s under 270 volts and exceeds 330 volts at the top end. Such an unusually low voltage battery configuration puts a lot of strain on the DC fast charger, which must operate at relatively high current levels.

For example, to supply 150 kW of power at 288 volts, the charger would have to send over 520 amps, which might be above the charger’s capability. This means that in some cases, the charging power will be limited not by the charger’s power peak — there are many 150+ or even 350-kW chargers — but by the charger’s current peak. Thus, the 150-kW charging level will not be seen too often or only for a specific part of the charging session at ultra-high-power chargers with a high current limit.

Charging Curve

Our DC fast-charging test was conducted at three separate stations, each from 10% to 80% SOC:

• Electrify America (150 kW)
  [Most of Electrify America’s chargers are 350-kW ones, but we wanted to see the results at a lower-power unit]
• Tesla Supercharger (250 kW) with a NACS-to-CCS1 adapter
• EVgo (350 kW)

* The session at the Electrify America site was from 9% to over 79% SOC. We used the data from 10% SOC and estimated the time for 80% SOC, as it had minimal impact on overall results.

** On rare occasions the car or the charger reports a bugged SOC number (it increased from one value to another within seconds). It happened both at a Supercharger and at an EVgo site without any meaningful impact on the results.

The first graph presents the charging power curve from 10% to 80% SOC for all three sessions. The curve on the Electrify America (150 kW) charger differs significantly from the two other higher-power chargers.

It’s crystal clear that a 150-kW charger is unable to deliver enough current for a low-voltage battery system and it limits the power to 96 kW. The charging curve is almost perfectly flat. At such power, the battery’s temperature probably remains within its limits.

The situation is completely different with the EVgo (350 kW) charger. It can deliver the maximum current requested by the car and reach 157 kW. There is a step power reduction at about 35% SOC to about 125 kW. Around 43% SOC, the power started to decrease significantly, reaching just 70-80 kW for some time (between 51% and 68% SOC). It reminds thermal throttling (thermal derating). At a later point, the power once again increased, peaking at 86 kW.

The charging session at a 250-kW Tesla Supercharger is reminiscent of the one at EVgo. The peak power was a bit lower (153 kW), but the general shape appears similar. In the second part of the session, the Supercharger stayed around 125 kW longer than at EVgo, but the following power reduction was a bit deeper.

The average 10-80% SOC charging power for the three tests were:

• Electrify America (150 kW): 92 kW
• Tesla Supercharger (250 kW): 108 kW
• EVgo (350 kW): 103 kW

C-Rate

Assuming that the vehicle has an 85-kWh battery, the Chevrolet Equinox EV’s C-rate peaked at over 1.8C (at EVgo and the V3 Supercharger). At the 150-kW charger, it was just 1.1C.

Info: The C-rate indicates the correlation between the charging power and the battery pack capacity. A value of 1C would mean that the power value in kW is equal to the battery pack capacity in kWh and that at such power (current) rate, the battery would be fully recharged in 1 hour. The higher the C-rate, the higher the load on the battery and the faster it charges. A flat 2C would translate into a 30-minute charging session (0-100% SOC).

However, the average 10-80% SOC were much closer to each other:

• Electrify America (150 kW): 1.08C
• Tesla Supercharger (250 kW): 1.27C
• EVgo (350 kW): 1.21C

Charging Time

The charging session from 10 to 80% SOC took 38.5 minutes at the Tesla Supercharger and almost 40 minutes at the EVgo station. The session took several minutes longer at the 150-kW Electrify America charger. The lower-power chargers are simply not well-suited for the Chevrolet Equinox EV.

It’s a bit surprising that the session at EVgo wasn’t the shortest, considering its initial advantage. However, the difference between charging at EVgo and at the Supercharger is very small.

The average 10-80% SOC charging power for the three tests were:

• Electrify America (150 kW): about 44 minutes
• Tesla Supercharger (250 kW): 38 minutes and 30 seconds
• EVgo (350 kW): 39 minutes and 51 seconds

The time-based chart reveals that the peak charging power of around 150 kW is available for roughly 10 minutes. Then, for another 5-10 minutes, the vehicle can charge at 125 kW or so.

Range Replenishing Rate

The 2024 Chevrolet Equinox EV 2RS FWD has an EPA Combined range of 319 miles. State Of Charge also achieved 303 miles in a 70 mph range test. This allows us to calculate the range replenishment rate for each charging session.

At the 150-kW charger, assuming EPA range, it’s ultra-flat 5 miles per minute of charging.

Charging at a V3 Tesla Supercharger can translate into a much better result of 6.6-6.8 miles per minute over the first 20 minutes. Then, the speed decreases to less than 5 miles per minute.

At the 350-kW EVgo charger, the results are the highest initially, regaining almost 8 miles per minute during the first 10 minutes of charging. Later, it’s less than 6 miles per minute and only 4 minutes per minute in the third 10-minute period.

It’s interesting that EVgo got the best results in the first part, but the worst in the third part.

How Long To Add Driving Range

Alternatively, we could ask how long it would take to add a certain number of miles. In the case of the 150-kW charger, it takes almost 10 minutes to replenish an additional 50 miles of range. This rate is flat, so adding 150 miles requires almost half an hour.

At the V3 Tesla Supercharger, it’s possible to add 100 miles of range in less than 15 minutes. This type of charger outpaces the 150-kW charger by several minutes.

The EVgo station was slightly quicker than the Tesla Supercharger in the initial part of the session and slightly slower in the later part. There we found that 100 miles of range can be replenished in less than 13 minutes. However, the addition of 200 miles requires 34 minutes, compared to 33 minutes at the Supercharger.

DC Fast-Charging Matrix

As always, we also have the DC fast-charging matrix, which summarizes the entire charging session. It lists several main parameters: time, average charging power, the number of replenished SOC percent points, kWh of battery capacity, and miles of EPA Combined range added between certain starting and final SOC points.

This time, we have three separate charts, one for each session.

Please remember that the results might differ depending on a variety of factors, including the starting point of the session (which could shift the charging curve), charger, temperatures (ambient, that of the charger and its cable, and battery), and car (exact version, age, battery state-of-health, and software version).

The session at the 150-kW Electrify America charger is full of green boxes, as the charging power was ultra-flat.

In the case of the 250-kW Tesla Supercharger and 350-kW EVgo station, we can clearly see that there are three areas – light green, dark green, and yellow, indicating a gradually slowing average charging power. Charging longer translates into lower and lower average charging power and range replenishing speed.

Summary

The tests once again confirmed that the 2024 Chevrolet Equinox EV’s charging performances are so-so and that’s probably still fine as long as the price is attractive enough.

At the same time, it was easy to achieve the promised specs — a peak power of 150 kW and the ability to replenish 70 miles of range in 10 minutes — at high-power chargers.

At the 150-kW charger, which can’t deliver enough current at low voltage, charging performances are compromised as expected. This translates to a several minutes slower charging session. If you have to DC fast charge frequently, this might matter.

The thermal throttling probably had some impact on the charging sessions (at EVgo and the Supercharger), so there is a potential for an upgrade in future versions of the battery system and cooling system. However, the main weak point is the low voltage in the current pack configuration — more appropriate for General Motors’s larger EVs with larger batteries.

By the way, there is absolutely no sense in charging beyond 80% SOC if not required, because the charging power drops significantly (see previous report from 0-100% SOC and 20-80% SOC sessions).

Check more of our DC fast charging analyses here.