Don’t Waste a Sale: How To Size a Forklift Battery

“What battery do we need?” asks your latest potential client.

They figure that’s a simple question for a forklift battery expert like you, but you’re starting to sweat. You don’t know the right answer. Sure, you can project enough confidence to make a guess. If you’re wrong, you’re going to have an angry customer on your hands. Yet, if you stall long enough to call the vendor, you’ll look incompetent. Either way, you’re gambling with your credibility and your commission.

This no-win scenario is entirely preventable.

Recommending a right-sized forklift battery requires a basic understanding of forklift power requirements and the forklift’s application. However, with just a few questions, you can gather all the information you need to look like the battery expert your clients expect you to be.

Read on to learn how to size a forklift battery the right way.

Battery Basics: Understanding Battery Terminology

Competency consistently ranks as the most important factor in sales success.

More specifically, your clients must believe you know what you’re talking about. Understanding the basics of batteries is essential to your credibility. If you’re new to motive battery sales and haven’t talked about volts and amp hours since high school science class, or if you’re fumbling your way through basic terms, it could cost you a potential sale.

So, let’s demystify the terms you’ll need to intelligently discuss forklift batteries.

Voltage

Think of voltage as electrical pressure.

It is the force that drives an electric charge through a circuit. Conceptually, voltage is a lot like water pressure. The higher the water pressure, the faster the water flows. Similarly, the greater the volts (V), the stronger the force pushing current through the circuit. So, a 48V battery drives more current than a 36V battery.

The forklift model determines battery voltage.

Electric forklifts commonly require one of the following voltages:

• 24V
• 36V
• 48V
• 72V
• 80V

Choosing the wrong voltage isn’t a sizing mistake; it’s a glaring mismatch.

Getting this one wrong will undermine your position as an expert.

Amps

Amps (A) measure the flow of electrical current.

Continuing with our water analogy, amps are like the volume of water moving through a pipe. The greater the amps, the more current flows through a circuit. Voltage and resistance determine amps. If voltage is the water pressure, electrical resistance (ohms) is the pipe diameter. Water pressure forces water through, but a narrow pipe might still restrict the flow.

By themselves, amps don’t often come up in forklift battery discussions, but they’re vital to understand amp hours.

Amp Hours

Like voltage, amp hours (Ah) are crucial for selecting the best battery.

Amp hours measure battery capacity. This represents how much current a battery can produce over time. In that way, it’s similar to a water tank. Water pressure and pipe diameter determine the flow rate, but tank volume determines how long it will last. Similarly, voltage and electrical resistance determine the amps, but amp hours determine how long the battery lasts between charges.

Amp hours are simple to calculate.

Multiply the amp draw by the usage hours to determine the minimum amp hours needed. For example, a forklift that draws 200A and runs for 8 hours theoretically requires a minimum battery size of 1,600Ah. At least, that’s true of a perfect system, but real circuits are far from perfect.

As a result, a few real-world factors influence right-sizing.

Forklift Battery Right-Sizing

Consider these factors when quoting a forklift battery.

Battery Efficiency

Electricity is only one type of energy.

A perfect circuit retains all its energy as electricity. However, no such circuit exists. In reality, some electrical energy is converted to heat energy. This affects battery efficiency. If a battery is 90% efficient, it loses 10% of its electrical energy to heat. In terms of capacity, a 90% efficient battery only provides 90Ah out of every 100Ah.

Accounting for inefficiency is essential when selecting batteries.

Depth of Discharge

Depth of Discharge (DoD) affects battery lifespan.

To maximize a battery’s usable life, never use 100% of a battery’s power. DoD represents the percent of a battery’s rated capacity used. For example, if the depth of discharge is 20%, the operator used 20% of the battery’s capacity.

Every forklift battery has a DoD rating.

This rating indicates when a battery needs charging to maintain optimal lifespan. Depleting a battery beyond its DoD rating dramatically reduces its functional life. Consequently, a battery with an 80% DoD rating needs recharging when 20% of its capacity remains.

While DoD doesn’t affect a battery’s rated capacity, it does limit the usable power.

General Battery Sizing Example

Now, we’ll put it all together using the forklift from our previous example.

To start, let’s list what we know about the forklift’s requirements:

• The forklift draws 200A.
• It runs throughout an 8-hour shift.
• It needs at least 1,600Ah (amps x hours) to last the whole shift.

Next, let’s look at two different batteries:

• Battery A is 80% efficient with a 50% DoD rating.
• Battery B is 90% effective with an 80% DoD rating.

As a result of these real-world factors, each battery’s rated capacity will exceed 1,600Ah.

Calculating the minimum rated capacity for each battery requires two steps.

First, divide the minimum amp hours by the battery’s efficiency. Be sure to convert the percentages to decimals first.

• Battery A. 1,600Ah divided by 0.8 equals 2,000Ah.
• Battery B. 1,600Ah divided by 0.9 equals 1,780Ah

These are the minimum rated capacities after accounting for efficiency.

Second, divide the minimum rated capacity by the DoD rating.

• Battery A. 2,000Ah divided by 0.5 equals 4,000Ah.
• Battery B. 1,780Ah divided by 0.8 equals 2,225Ah.

Consequently, Battery A needs a rated capacity of at least 4,000Ah to provide 1,600Ah, whereas Battery B needs a 2,225Ah capacity.

Forklift Battery Type Affects Right-Sizing

The differences between battery chemistries also affect battery selection.

Typical lead-acid forklift batteries offer 70% to 80% efficiency and DoD ratings of 50% to 80%. To meet power demands, these batteries may require higher capacities than those of other chemistries. However, they are less expensive than lithium-ion. Consequently, a right-sized strategy might focus on battery swapping instead of a single large-capacity battery.

Lithium-ion forklift batteries offer different benefits.

These batteries are usually 90% to 95% efficient with a DoD rating around 80%. Consequently, a smaller capacity lithium-ion battery can match a larger lead-acid battery. Additionally, lithium-ion batteries can benefit from opportunity charging, making them ideal for multi-shift operations. That said, they are more expensive.

Ultimately, the decision between lead-acid and lithium-ion is more about client needs than capacity.

Right Size Your Battery Sales

Voltage and amp hours are only part of right-sizing.

Many operational factors will further narrow choices and recommendations. The “5 Critical Questions to Ask Before You Quote Any Battery” sidebar covers the basic information necessary for an accurate quote.

Gathering this information directly impacts the success of your sale:

• Professional reputation. Clients are more likely to trust knowledgeable sales reps. Providing an inaccurate quote or failing to gather vital information undermines that trust. However, collecting critical information at first contact shows experience and competence.
• Prevent oversizing. Incomplete information can lead to oversizing. The rep can’t accurately calculate the minimum amp hours. So, they overestimate. Oversizing adds unnecessary weight, suggests a battery that might not fit in the forklift’s compartment, and eats up the client’s budget.
• Avoid undersizing. Underestimating battery requirements makes frustrated clients. An inadequate battery fails sooner, leading to uncomfortable warranty conversations.
• No unnecessary upselling. Application information helps you recommend the best battery chemistry for your client. You can recommend budget-friendly options that fit the application, or advocate for upgrades that offer significant advantages. This “Honest Guide” approach builds trust.
• Smooth purchase experience. Right-sized battery recommendations create happier clients. The batteries meet or exceed expectations, leading to repeat business and referrals.

Bottom line: never skip the information gathering step. Without it, you’re setting yourself up for failure.

GECI Is Your Motive Power Safety Net

Whatever your experience with forklift batteries, we’re here to empower you.

This article provided a foundation for strong, competitive quotes. Yet, there’s always more to learn. Motive power technology and your customer’s needs evolve constantly. Challenging requests and nuanced questions crop up all the time.

We’re your subject matter expert behind the scenes.

When things get complicated, don’t sacrifice your expert status. Reach out to our professionals for fast, reliable answers. When you need pricing options, our pricing and inventory structure allows you to quickly quote multiple price points. If you’re stumped on the battery model, send us the specs. We’ll send you our recommendations and a quote in minutes, so you can field even the most challenging requests. You lift up your clients every day. Let us do the same for you.

To learn more about forklift battery right-sizing or to request a quote, contact us online or call us at (877) 914-8999.

Further Reading

Forklift Batteries

Forklift Battery Chargers