Untold Battery & Charging Info of the Electric Hummer

The original Hummer is a BEAST of a truck. But, the electric Hummer is more impressive with its battery and charging capabilities.

Because let’s face it, who would’ve thought we’d even have an electric Hummer? Not so long ago, the public viewed Hummer vehicles as monstrous pollution machines. They guzzled gas like it was going out of style.

Look no further than the H1 Hummer. It gets 10 miles per gallon of gas, and weighs upwards of 8,000 pounds. In comparison, a Ford F-150 truck weighs a measly 4,000 to 5,000 pounds.

This now perfectly sets the stage for discussing the Hummer EV. I’m going to discuss the electrical engineering behind parts of this Hummer. And before you tell me, I know and I get it. The Hummer EV isn’t aerodynamically shaped and it still resembles a brick.

Still though, you can’t dismiss the awesome built-in power in the Hummer by GM, the manufacturer. They’ve designed advanced battery systems to give the Hummer a full makeover. In fact, this new luxury enviro-conscious rebranding is a twist of fate.

Can the Hummer EV rebrand itself to create a new identity?

To discuss the potential of the Hummer EV, I’m going to cover the following subjects:

  • Power specs
  • Charging costs
  • Driving range
  • Charging speeds

Hummer EV power specs

hummer electric vehicle
Photo Credit: Kala4i4ek

The electric Hummer has three electric motors that power its e4WD system. The e4WD system is just the cool sounding way of saying all-wheel drive.

In this power design system, there’s one motor located in the front, and two in the rear. And each motor has a rating of 250 kW. So this behemoth vehicle has a max power output of 750 kW or about 1,000 horsepower!

To point out, this peak 1,000 HP is only sustainable for short durations in the “Watts to Freedom” mode. For example, for going from 0 to 60 mph in 3 seconds!

But what’s even more attention-grabbing is the Hummer’s battery system.

Battery system calculations

The big question is, how does something as huge as a Hummer move so effortlessly? A gigantic battery of course!

Let’s do the battery calculations, to piece together the Hummer’s battery system. The Hummer EV has 24 cells x 24 modules = 576 cells in total.

Then each battery cell has a rating of about 100 Amp-hours. This calculates to 576 cells x 100 Amp-hours = 57,600 Amp-hours (Ah).

Let’s pause and make note that Amp-hours x Volts give us Watt-hours (Wh). All we’re doing here is using the P = VI equation, where P is the power measured in watts. To point out, 1000 Watts = 1 kilo-Watt (kW). And kWh is how we define battery energy storage.

Next, let’s assume the nominal voltage of a lithium-ion battery is 3.60-volts/cell. The calculation then becomes 57,600 Ah x 3.6-volts = 207,360 Wh or 207.4 kWh!

To put a 200+ kWh battery pack rating into perspective, the following are specs from other EVs:

TABLE

Important Note: GM linked 12 battery modules together creating a 400-volt battery pack. Next, they connected two 400-volt packs in parallel, totaling 24 battery modules.

Hummer EV charging cost

The charging cost depends on the EV charger type you use. To do a rough comparison, we’ll crunch some numbers with Level 2 and Level 3 chargers.

To start, the average electricity rate was 13.7 cents per kWh in February 2021. We’ll use this electricity rate to calculate the cost of fully charging at home. And the 0.87 constant is the assumed charger efficiency.

(207.4 kWh / 0.87) x $0.137 per kWh = $32.66

Next, Tesla’s Supercharger costs about $0.26 per kWh. So we can safely assume the same cost for any other DC Fast charging to charge the Hummer EV.

(207.4 kWh / 0.87) x $0.26 per kWh = $61.98

To put these costs into perspective, let’s compare to the cost of filling up a gas-guzzling Hummer.

Vehicle Charger/Fuel typeBatter/Tanks sizeCost of fuel (2021)Full fueling costCost/mile
Hummer EV (350 mile range)Level 2 charger207.4 kWh$0.137/kWh$32.66$0.09/mile
Hummer EV (350 mile range)Level 3 charger207.4 kWh$0.26/kWh$61.98$0.18/mile
Hummer H1 (250 mile range)Diesel25 gallons$3.249/gallon$81.23$0.32/mile
Hummer H2 (320 mile range)Premium gasoline32 gallons$3.028/gallon$96.90$0.30/mile
Hummer H3 (322 mile range)Premium gasoline23 gallons$3.028/gallon$69.64$0.22/mile

The EV cost savings is clearly evident compared to all the old Hummer models. But, the savings amount isn’t too attention grabbing given the Hummer is an EV. In fact, when you consider the purchase price of a Hummer EV, you quickly realize the lack of cost savings.

Breakeven cost comparison between a Hummer EV and Hummer H3

The “Edition 1” Hummer EV truck will cost about $106,000. A decent used 2006 H3 Hummer with 20,000 miles costs about $25,000. A cost difference of $81,000.

In our calculation we’ll assume you drive 13,500 miles per year. This is the average miles driven per year in the U.S. according to the U.S. Department of Transportation.

Hummer EV: 13,500 miles x $0.09 = $1,215 per year

Hummer H3: 13,500 miles x $0.22 = $2,970 per year

The difference in annual cost between the Hummer H3 and EV: $1,755 per year.

So to break even, it’ll take $81,000 / $1,755 = 46 years!

Yes, there will be a lot of other maintenance costs with a used H3 Hummer. But my point is, you’re not purchasing a Hummer EV for the cost savings. But to be fair, most people who purchase a Hummer EV just want a badass rugged EV!

To learn more about the cost to charge an electric vehicle, read here.

Hummer EV driving range 

hummer-electric vehicle off roading
Photo Credit: Kala4i4ek

GM has thrown out a driving range of 350 miles for the Hummer EV. As a comparison, the following is the driving range of gas-fueled Hummer models:

  • H1: 250 miles
  • H2: 320 miles
  • H3:  322 miles

The Hummer EV has a slight edge over its predecessors. It’s important to note though, the weight of the Hummer models is important to know. Otherwise, it’s not an apples-to-apples comparison.

Now, how about comparing the driving range to other electric vehicles?

The below table is the driving range of popular EVs, including Tesla’s Cybertruck. And the calculated charging costs are using Level 2 chargers.

Electric vehicleBattery usableRangeFully charge costCost per mile
Hummer EV (tri motor)207.4 kWh350 miles$32.66$0.093
Cybertruck (tri motor)200 kWh500 miles$31.49$0.063
Model 3 (Long Range)82 kWh353 miles$12.91$0.037
Model S (Long Range)90 kWh412 miles$14.17$0.034
Model X (Long Range)90 kWh360 miles$14.17$0.039
Model Y (Long Range)72.5 kWh326 miles$11.42$0.035

Not surprisingly, the Hummer EV isn’t the most efficient vehicle in the list, and it’s clear why. It’s HEAVY and it has the least aerodynamic shape. And therein lies the problem. The Hummer brand is synonymous with having the shape of a brick, which leads to a poor drag coefficient.

Without a doubt, if GM would cut the weight of the Hummer EV, they could increase the driving range to near 500 miles. But then, the Hummer would lose it’s iconic design and edgy personality.

Hummer EV charging speed

We already know the battery design is two 400-volt packs connected in parallel. But what’s awesome is, you can plug the Hummer into an 800-volt charger too.

How you ask? The internal vehicle electrical components reconfigure. The Hummer connects the two 400-volt battery packs in series. And series connected batteries add up together, 400-volts + 400-volts = 800-volts.

So you can connect to an 800V DC Fast charger rated 350 kW and draw about 250 Amps. Let’s crunch the numbers to see how this would play out and impact the charging speed.

Charge time = \dfrac{\text{battery capacity}}{\text{charger power x 0.87}} = \dfrac{\text{207.4kWh}}{\text{350 x 0.87}} = 0.68 hours

So, the charge time is roughly 41 minutes to go from a depleted battery state to full charge.

To point out though, the 350 kW peak power lasts only for a short duration. You’ll never get 350 kW over your entire charge. The power naturally tapers off as the battery charge increases.

You can see this charging profile in the below table showing peak power versus charging time. I used charging data from a 250 kW DC fast charger. The table shows over time as the EV charges, the peak power decreases. This is a very typical charging profile.

Charging Time Peak power
5 minutes245 kW
15 minutes225 kW
20 minutes200 KW
30 minutes135 kW
40 minutes85 kW
50 minutes50 kW
60 minutes35 kW

Now, let’s compare the charging speed using the other EV charger types.

Charger typePeak powerCharging time
Level 1, 120V-1∅1.4 kW170.3 hours
Level 2, 240V-1∅7.6 kW31.4 hours
Level 3, 480V-3∅250 kW0.95 hours
Level 3, 800V-3∅350 kW0.68 hours

To better understand how to calculate charging speed, read here.

Conclusion

The Hummer is back and with a vengeance!

Especially, when you consider not so long ago, Hummers were mascots for global warming. And yes, the electrical Hummer still isn’t the savior to the “destruction” of Earth. It’s beefy and anything but efficient given its non-aerodynamic design. Also, there’s a camp who focuses on the emissions from manufacturing the trucks, or any EV for that matter.

BUT, with all that said, the Hummer EV is still miles ahead of its predecessors. Plus, this modern makeover may make Hummers appealing to a whole new audience. An audience who shuns electric vehicles, and prefers large rugged gas-guzzling trucks.

In the end, the truck is simply awesome engineering. Engineers are making great strides in advancing electric vehicles. And what better way than making the almighty gas-guzzling Hummer go “green.”

What are your thoughts on an all electric Hummer? What amazes you the most about the engineering behind the electric Hummer? Do you think GM should have made the Hummer shape more aerodynamic?


Featured Image Photo Credit: Kala4i4ek (Photo Cropped)

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