Welcome to your crash course in
understanding batteries
Welcome to your crash course in
understanding batteries
While Battery Electric Construction Equipment has been around for quite some time, there is still some uncertainty when it comes to electric excavators, electric skid steers, & others. Why are runtimes not specific? How does temperature affect a battery? How much power do batteries really provide for equipment? Everything you could need to know about battery-electric construction equipment can be found here.
Understanding
Runtimes
If you've been looking for electric construction equipment, you've probably been looking for how long the equipment will run on a single charge. Which makes sense because it's a pretty important factor to consider for the work needing to be done on your upcoming jobsites. Any machine that can't be operated for a full working day will end up being pretty useless for the contractor using it.
So How Long Can I Work?
What you will find (in most cases) is that electric construction equipment tends to list a range of runtimes like 6-12 hours instead of a hard number like 9 hours.
So why do we do this? Lets compare this to your cell phone. Your cell phone battery can last all day long if you're only using it for texts, phone calls, or emails. However, if you try to play a game on your phone, your battery has significantly less runtime because it uses more power to run the game.
The same can be done with electric construction equipment where certain tasks like breaking concrete with a hydraulic hammer, or carrying heavy loads in a concrete buggy will require more power and lead to a shorter runtime.
So the next time you see a range of runtimes for electric equipment, just remember that this isn't a deception, and it actually the most honest answer that a manufacturer of battery powered equipment can provide.
Types of Lithium Ion
Batteries
There are many types of Lithium Ion batteries, ans as technology is ever evolving, those chemistries are changing as well. With each chemistry, there are pros and cons for each one. Lets dive into a few of the most popular types, or chemistries, of Lithium Ion Batteries.
LiFePo4 (lithium iron phosphate)
Lithium Iron Phosphate is the chemistry better known as LiFePo or LFP. LFP batteries are known for their long life span, safety, and stability. They have a lower energy density compared to other types but are widely used in large-scale stationary energy storage, electric vehicles, and backup power systems due to their durability and safety.
NMC (Nickel Manganese Cobalt)
Nickel Manganese Cobalt is the chemistry better known as NMC. NMC batteries are known for their high energy density and good thermal stability. They are widely used in electric vehicles, medical devices, and power storage systems. NMC batteries balance energy density with safety and longevity, making them suitable for a wide range of applications.
LCO (Lithium cobalt oxide)
Lithium Cobalt Oxide is better knows as LCO. These batteries offer high energy density and are commonly found in mobile phones, laptops, and digital cameras. However, they have relatively short life spans and can pose safety risks if damaged or improperly handled.
How to choose a battery chemistry?
When deciding which type of Lithium Ion battery pack to use in a product, its important to understand all ot he advantages and disadvantages of the particular chemistry. Each type of lithium-ion battery has its own unique advantages and is chosen based on the specific requirements of the application, including cost, weight, energy density, safety, and lifespan considerations.
Lithium VS.
Lead Acid
Batteries are nothing more than a way to store energy. The 2 most popular types of batteries being used today are "Lead Acid" and "Lithium".
So now you're wondering, "Which is better?" Well we're here to tell you!
Cost
When it comes to purchasing equipment, cost is always an item that comes up. There are some significant differences in the cost of Lead Acid batteries vs the cost of Lithium batteries.
Lead Acid batteries have been produced on a massive scale for significantly longer than Lithium batteries has, therefore reducing the manufacturing costs. The cost of materials in Lead Acid batteries are also significantly less.
Overall, Lithium Batteries could be as much as 3x-4x the cost of Lead Acid Batteries depending on the size and configuration.
Performance
As we know, batteries are just a place to store energy. How that energy is used is dependent on the components the battery is supplying energy to.
As Lead Acid batteries lose charge, the power draw or the ability to supply amperage drops. This is why a forklift with a lead acid battery my drive slightly slower with 50% charge vs 100% charge. A lithium battery will operate with the same speed and efficiency at 100% or 10%
Service
Lead Acid batteries traditionally have more service that is required to keep them operating at optimal performance. Making sure distill water is covering the lead plates, checking the specific gravity and having the proper charging cycles are all things that need to be considered.
Lithium batteries have significantly less service requirements. The main thing is to make sure to have proper charging cycles and never let the battery run to a 0% charge.
How temperature
affects batteries
Extreme Cold
Remember that all batteries are simply a place to store energy through chemical reactions? Well at cold temperatures, the chemical activity within a battery slows down, making it harder for the battery to deliver power. This can lead to a reduction in runtime because the battery cannot release its stored energy as efficiently.
Cold temperatures also increase the internal resistance of the battery, further reducing its efficiency. Higher resistance means that the battery has to work harder to provide the same amount of power, leading to quicker depletion.
Because cold weather increased the chemical resistance within the battery pack, recharging batteries in cold conditions can also be problematic. The reduced chemical activity can prevent the battery from recharging fully. Instead of recharging to 100%, the pack might only be able to recharge to 80% or 90% leading to a shorter usable life between charges.
Extreme heat
How to mitigate temperature risks
Many battery electric vehicles and products incorporate thermal management systems to keep batteries within an optimal temperature range. These systems can use air or liquid cooling to dissipate excess heat or insulation and heating elements to keep batteries warm in cold conditions. Regulating the temperature of the battery packs is the key to long term health of the battery packs.
Avoiding charging or storing batteries in extreme temperatures is also an important factor in the long term health of batteries. Charging in moderate temperatures and storing in cool, dry places can help mitigate the adverse effects of extreme temperatures. If you're working near a blast freezer or a kilt melting steel, its best to remove the machine from that area for it to charge.
We previously discussed the differences in battery chemistries. Some types of battery chemistries are more resistant to extreme temperatures than others. For example, LFP or Lithium Iron Phosphate batteries tend to perform better in a wider range of temperatures compared to other chemistries.
Why is zero emissions
important?
Battery Electric Equipment is not for everyone. Its not for every jobsite or every contractor. But why is it important and where should you be looking to implement it. Lets dive in ...
Benefits of Battery Electric
Lets start with the basics? Why even entertain the idea of using a battery electric machine? Some project sites need zero emissions, some project sites have a restriction on fossil fuels due to risk of contaminants and some might be looking for a complete net zero build. But what is driving that decision?
Working Indoors
When completing work indoors, confined spaces can create many obstacles to a safe, efficient and profitable project. The first is a lack of labor in the construction industry. Finding team members to complete these projects is an ongoing issue within the construction industry. Battery powered machines have the ability to complete tasks inside of confined spaces at a more efficient pace than traditional human labor. Its the same reason we don't dig foundations for buildings by hand anymore. Machines can complete tasks in a fraction of the time that humans can, making jobsites safer and more efficient.
Risk of Contaminants
Even facilities that manufacture the goods we buy every day need to be updated and maintained. You wouldn't want a machine with a gasoline engine handling your raw food as its being processed.
Battery electric forklifts have been used for years in food processing facilities around the globe, but now with the advancement in technologies, we can expand that to all types of machines and facilities. It could be using a mini excavator inside of a greenhouse or a track loader to clean under a conveyor system inside of a manufacturing plant, battery electric equipment can reduce the risk of contaminating the goods we use every day in our homes.
the net zero jobsite
Global warming is an issue we are all facing in the coming years and with recent legislation, there is a push toward Net Zero jobsites. Net Zero means that there is a complete carbon offset or the jobsite have zero carbon footprint. Using battery powered machines can allow for the contractor to have a completely renewable energy system.
A combination of solar panels powering a battery electric generator and using 100% battery powered machines can easily leave zero carbon footprint. While this is not the norm of construction today, this is the norm of the construction site of tomorrow.
long term vs short term costslead acid vs lithium
With every decision comes Pros & Cons. So lets dive into the long term and short term costs of owning a battery electric machine powered by either a lead acid battery or a lithium ion battery
up front costs
As we touched on in our "Lithium vs Lead Acid" post, the up front cost of a Lithium Ion battery is about 3-4 times more expensive than a Lead Acid battery depending on the size and configuration. There are a few reasons for this:
1) Lead Acid batteries have been produced for longer and make up a larger percentage of the worldwide consumption. Due to the scale of manufacturing, the cost is less to produce lead acid battery packs
2) The cost of mining Lithium Ion battery components is more expensive than the cost of mining the components of Lead Acid batteries
3) There are more electrical components inside lithium batteries. A BMS (Battery Management System), contactors, relays and additional safety features all contribute to the increase manufacturing costs.
miantenance & service costs
In order to properly maintain a lead acid battery, there are several things that should take place on a consistent basis. All batteries are chemical reactions that take place to store energy. Lead Acid batteries should have that chemical balance maintained consistently. Lead Acid batteries also have to maintain a specific distilled water level in order to completely cover the lead plates inside the battery pack. This ensures the chemical reactions are taking place accordingly.
Lithium Ion batteries are virtually maintenance free. simply make sure to properly charge the packs and the BMS takes care of the rest.
lify cycles and life span
overall assessment
Overall, Lead Acid batteries will cost you less up front and more over the long term while Lithium Ion will cost you more up front but less over the long term.
Each has its pros and cons for individual scenarios based on what your preferred long term plan for the battery electric machine is.
What Are Life cycles?
why do they matter?
The life cycles of a battery are important is looking at daily usage and total overall cost of ownership.
Daily Usage
Lead Acid and Lithium Ion batteries function much differently during daily operations when thinking about the total life cycles of the battery pack.
Understanding
Amperage & Current
You may look at a 300v battery and think its so much bigger and more powerful than a 48v battery, but you could be wrong. The thing that differentiates battery powered machines is the amount of amperage of the pack. So what is amperage and what do we mean by current?
1st law of thermodynamics
When talking about amperage and current, its important to understand what the 1st law of Thermodynamics states, which is ΔU=q+w.
ΔU = the total change in energy
q = the heat exchange in the system
w = the work done in the system
This equation means Energy cannot be created or destroyed, it can only be converted from one form to another through the transfer of heat.
So What is amperage?
In its simplest definition, amperage is the strength of the current in which the electricity is flowing from one component to the other, expressed in Amperes or amps. In battery electric machines, amps are pulled from the battery to the electric motor in order to make the machine move. The size of the battery pack is typically calculated in kWh (Kilo Watt Hours) which is the Voltage, multiplied by the Amperage. Our CMX18 battery electric mini excavator has a 20.16kWh battery pack which comes from a 48v battery at 420amps.
How does amperage affect runtimes?
The amount of amperage that a battery holds has a close relationship to the total amount of power in the battery. Each function draws current (amperage) while operating. The harder the function, the more current is needed to make that function happen.
So the runtime of a battery powered skid steer with a floor scraper is going to be less than when it operates with a regular bucket because the floor scraping function requires more current to make that function happen.
What happens if we draw too much amperage?
Within a battery powered machine, energy is transferred from the battery to the electric motors in order to create movement. The harder the function, the more energy needs to be transferred which creates more heat within the system
The harder the function of the machine, the more current is needed to make that function happen so more amperage is drawn from the battery. Because energy cannot be created or destroyed, merely transferred, as amperage is moving from one component to the other, heat is created in the system.
If too much heat is created, the system could shut down to protect the electrical components from burning up. Each of our battery electric machines have built in safety features to protect the machine and the operator from doing long term damage to the components due to intense heat.
