GM Ultium Battery — A Flexible Architecture For Next Generation EV
By: Vincent Tabora
Tags: Electric Vehicles, Automotive, Engineering, Battery, Technology

Automaker and established brand GM (General Motors) have plans for growing their EV (Electric Vehicle) division. They offer a high capacity battery called the Ultium, a system that will be installed in their next line of EV. This complements an all new modular platform that will make up an ecosystem for GM’s third generation EV.

According to GM President Mark Reuss:

“Thousands of GM scientists, engineers and designers are working to execute an historic reinvention of the company. They are on the cusp of delivering a profitable EV business that can satisfy millions of customers.”

GM are well known for their cars and trucks, which they can produce at scale. EV are a totally different type of product, which has not yet been well established by any car company. The closest to it in 2020 would have to be Tesla, Inc. Tesla, an EV car company, has faced struggles of their own in what CEO Elon Musk called “production hell”. Getting EV prices down to a selling point for mainstream consumers is the challenge of how to produce large quantities cheaper and more efficiently.

One of the components of an EV that can be scaled to meet production demands is the battery. The problem is the cost of producing batteries tends to be high, so if automakers want to sell affordable EV they can cut costs by producing cheaper batteries. That is what GM plans to do based from their Ultium battery announcement.

The Ultium

The Ultium battery was developed with LG Chem (a part of LG Corporation of South Korea) as a proprietary system that use large-format cells with a smart cell design. The partnership shows GM has trust in LG’s expertise in battery technology. Two features LG Chem provide are fast charging and longer range battery for EV. The battery is in line with zero emission vehicles which GM wants to meet to offset their gasoline vehicle carbon emissions. This is one of the goals of GM’s “all electric future”.

The Ultium battery pack (Source GM)

The battery design requires less Cobalt using advanced chemistry for higher energy density. The materials are fabricated into a module, with clusters of modules making up a battery pack. It is a totally new architecture that is not in use in the Chevy Bolt EV. The new battery design uses an NCMA (Nickel-Cobalt-Manganese-Aluminum) configuration which reduces 70% of Cobalt use while increasing capacity up to 60%. Tesla, during their “Battery Day” event, also announced a new battery design that aims to remove Cobalt and rely on Nickel.

Reducing Cobalt opens the doors for lower cost battery production that will rely on other more efficient materials like Nickel. The Cobalt is typically a part of the battery’s cathode. The redesign is aimed at reducing Cobalt and increasing Nickel. The Nickel is a good source of storing more energy, thus increasing the battery’s energy density to provide more power that can extend the range of EV. Cobalt is not as efficient, and is also much more costly because it is not an abundant resource. Another issue with Cobalt is the sourcing can be classified as a conflict mineral. That in itself can raise red flags when the source is coming from a region where it is being mined to support oppressive regimes.

This modular design is also flexible. The battery modules can be stacked up like bricks. The battery can be installed vertically inside semi trucks, SUV and crossovers, which are for high-energy stacking. For cars and performance vehicles it can be installed horizontally, with a lower center of gravity. The battery modules can be from 6, 8 and 12 per pack wired in series-parallel configurations. 12 modules would provide the most power and the longest range. These modules were also designed to simplify cooling, thus making the battery operate more efficiently.

The Ultium battery modular design, allows stacking of battery modules. (Source GM)

This provides the following benefits:

Estimated range up to 400 miles on a full charge

Capacity from 50 to 200 kWh (kilowatt-hours)

Lightweight so it does not become a burden to the vehicle

Space efficient allows more room to be utilized

Another feature that is a GM innovation is the battery management system. It will be highly computerized and supports wireless communications. The software will be developed to allow upgrading modules to provide more capacity for EV. The magic will all happen in the software, so this makes things like upgrades much simpler for car owners.

The purpose of building this battery is to cut costs and meet the $100/kWh for mass producing EV at scale with conventional cars. That is the price range where EV can fall to as low as $25,000. If price were the limiting factor, then more car buyers would consider an EV. The major benefit of course would be the removal of dependence on gas, so the slightly higher costs are the initial cost of purchase for consumers. Bringing prices even further down is the hope of attracting more interested car buyers in the market. Production of the batteries will be in GM’s facilities in Lordstown, OH (USA).

The New EV Lineup

The Cadillac Lyriq will be one of GM’s first EV to use the Ultium battery system. This will feature a battery pack with 100 kWh. This will provide more range at a lower cost for car owners. The battery will support DC fast charging at rates up to 150 kW (kilowatts).

The Cadillac Lyriq (Source GM)

According to Lyriq Chief Engineer Jamie Brewer:

“The Lyriq will have multiple charging opportunities and options for customers to pick from. We’ll offer both the Level 1 and Level 2 AC charging, and our Level 2 AC charging will offer up to 19 kilowatts, selectable charging. We’ll also offer DC fast charging, with over 150 kilowatts available. The customer will have the ability to choose where they charge, be it at home, at work or on the go, and how they charge and make the most of the time they have available to fill their battery.”

The electric Hummer is also included in this new lineup. It will be a modified version of the original Hummer design, with added truck features. The target date for this electric version is scheduled for 2022. This would be GM’s electric utility vehicle answer to rivals Tesla and Rivian.

A preview of the electric Hummer EV (Source GM)

According to CarAndDriver Magazine:

The Hummer EV SUT will ride on GM’s third-generation EV platform. The company also said that its truck-based models will have an 800-volt architecture with 350-kWh fast-charging capability. That indicates the Hummer could have a driving range of up to 400 miles.

Nikola Partnership

The Ultium battery has other projects for development. GM has signed an agreement with EV developer Nikola. The agreement is a partnership which will provide GM’s Ultium battery system and build the Nikola Badger, an electric pickup truck. This is in competition with Tesla’s Cybertruck and Rivian’s R1T. This should bring more excitement into the electric pick-up market, but the Badger is still a prototype (as of this posting). Tesla has already shown off a working Cybertruck during an event, while Rivian has been demonstrating the capabilities of the R1T. The competition have a working product for retail while GM and Nikola will still have to produce one (as of October 2020).

The Nikola Badger electric pickup truck (Source Nikola Motor Company)

It gets controversial because Nikola has been accused of fraud. A report was released by Hindenburg Research and it has negatively affected Nikola’s stock price. It may just be allegations, but it has already shaken things up. Nikola’s CEO Trevor Milton has even resigned from the company. Perhaps GM can still benefit from the design and develop the pick-up truck to their level of quality and standards if Nikola does not have the qualifications. That is to Nikola’s benefit while GM can still manage to save face by addressing the accusations of misleading information made by Nikola.

As far as the partnership goes, GM is moving forward despite the news. The Nikola Badger will not be the only project between the two companies. It also includes the development of the Nikola Tre, Nikola One, Nikola Two and NZT. They will use the Ultium battery system and Hydrotec fuel cells for these vehicles. GM also has a vested interest in Nikola since in the agreement, GM will own 11% of the company. It is a growth opportunity for GM to explore.

Synopsis

Building lower-cost and higher-density batteries can bring down the cost of EV significantly. This is what automakers like Tesla are hoping would bring greater adoption to expand into the auto market and increase EV demand. For GM this is a breakthrough that looks promising for EV development. They must play some catch up with Tesla though.

GM is also making their own electric pickup, which will surely be using an Ultium battery. There are reporters who have questioned why GM decided to partner with an EV company despite having plans to build their own electric pickup. Perhaps it is due to the benefits. GM is estimated to earn $2 billion from the deal in addition to the value of Nikola’s stock. Nikola also offers hydrogen fuel-cell technology and can provide a test bed for Ultium batteries.

GM have the facilities to manufacture at scale. The only concern here would be Nikola, since the reports of fraudulence does make you wonder about their technology. Despite those accusations, GM has to back their partnership with Nikola. That is for now, unless something else comes up that really proves Nikola is a dud.

GM’s downside seems minimal as this partnership will not severely affect them due to the news. GM never put up any money in the agreement, it will be Nikola who will have to pay GM for engineering and manufacturing services. GM might even be able to fix Nikola’s problems and that can open the path to meeting their goals of ramping up production for an emerging market. Overall, for GM this is a move to further their exposure in the EV sector.