The push towards electrification

The global urgency to electrify industrial vehicle fleets is growing. Power consumption in mining operations alone contributes some 0.4 gt of carbon dioxide equivalent annual greenhouse gas (GHG) emissions. This increases pressure to decarbonise operations, which is why many mining companies are turning to lithium-ion (Li-ion) batteries, as they come with a plethora of advantages that go beyond reaching zero emission targets.

Apart from reduced emissions, there are improved working conditions, reduced costs, and increased vehicle performance, amongst other benefits. Before exploring these, however, it is best to understand some Li-ion battery fundamentals and how they are reshaping the mining industry.

The three Li-ion battery chemistries recommended for mining applications

There are several Li-ion battery chemistries, though the six major ones powering various devices and vehicles are:

• Lithium cobalt oxide (LiCoO₂ [LCO]).
• Lithium nickel manganese cobalt (LiNixMnyCozO₂ [NMC]).
• Lithium nickel cobalt aluminium oxide (LiNiCoAlO₂ [NCA]).
• Lithium iron phosphate (LiFePO₄ [LFP]).
• Lithium titanate (Li₂TiO₃ [LTO]).
• Lithium manganese oxide (LiMn₂O₄ [LMO]).

Those best suited for mining applications will be discussed first, before looking at why other chemistries are not quite suited for this industry.

Lithium iron phosphate

One of the most popular chemistries for long charge cycle life and inherent safety, LFP is capable of enduring up to 10 000 charge cycles before being retired from vehicular use. It is also quite resistant to thermal propagation events and operates well in extreme temperatures. Since it does not require rare earth metals such as nickel and cobalt, it is also cheaper to produce.

When it comes to performance, LFP batteries maintain 100% capacity as they discharge during use, a feature that not all battery chemistries are capable of. Furthermore, even if the battery is completely depleted, some manufacturers state the battery will not suffer any damage, although it is not always recommended to do so.

The main drawback to LFP is its low specific energy. In e-mobility, specific energy is what provides the vehicle with high speed; however, in a mining context, this is rarely a requisite. This battery chemistry is ideal for large vehicles such as load, haul, and dump (LHD) trucks, loaders, excavators, bolting rigs, and drillers, since it is robust, durable, and cost-effective.

Lithium nickel manganese cobalt

One of the best all-rounders in the battery market, the NMC chemistry is widely used in the electric vehicle (EV) market. It is safe, performs well in low and high temperatures, can endure over 2000 charge cycles, and has high specific energy, unlike LFP.

The battery’s chemical composition can be configured to use less nickel and cobalt to lower production prices compared to other nickel-cobalt chemistries. There are different options, such as NMC811, which means the cathode is eight parts nickel and one part each manganese and cobalt. This reduces cobalt dependency and drives down the production cost. Similarly, there is the NMC622, which reduces nickel content but increases cobalt use. Both metals have faced supply issues in the past, and it can sometimes be costly to source them sustainably. Despite some savings, it could still be more expensive than non-nickel and cobalt-based chemistries.

However, it is an ideal chemistry for industries that operate in tight areas, such as the mining industry. NMC batteries can be 30% smaller than their LFP counterparts and still produce the same energy output, providing an excellent price-to-energy ratio. This means smaller batteries can be made for small vehicles (like mini excavators) without compromising design, while vehicles, such as 20 t trucks, can house these batteries with no weight increase concerns.

Enjoyed what you've read so far? Read the full article and the rest of the October Issue of Global Mining Review by registering today for free!

Read the article online at: https://www.globalminingreview.com/environment-sustainability/15112023/the-push-towards-electrification/