Forklift Battery Maintenance: Extend The Life Of Your Batteries

The average lifespan of a forklift battery is 5 years. But your forklift batteries can last longer — or shorter — depending on whether you practice proper forklift battery maintenance.

Unfortunately, by the time you ask: “Should I be doing more to care for my forklift battery?” it’s often already too late.

To keep your operations running smoothly (without dead batteries slowing you down and eating into your profits), here’s everything you need to know about properly caring for your forklift batteries from the first day they’re delivered to your door.

But First: 2 Types of Batteries Means 2 Types of Maintenance

There are two main types of forklift batteries, each with their own required maintenance plan.

The two main types of forklift batteries include: 

  • Lead-acid batteries
  • Lithium-ion batteries

Lead-acid batteries have dominated the market for years. In fact: in 2021, 90% of electric forklifts in operation were using lead-acid batteries.

But demand for lithium-ion is increasing across industries. In the automotive industry, demand increased by about 65% between 2021 to 2022. And that demand is unlikely to slow.

Why? 

Though lithium-ion forklift batteries carry a higher up-front cost, they come with some maintenance-related benefits:

      • Lithium-ion batteries are more energy-efficient
      • Charge up to 8x faster than lead-acid batteries
      • Never need to swapped out, and are easily opportunity-charged during operator breaks
      • Don’t slow you down as the battery discharges
      • Can reduce the number of forklifts required in multi-shift applications

And, most important: Don’t require as frequent maintenance or watering. 

Despite some of the positives of lithium-ion batteries, they don’t make sense for every operation or fleet. That’s why we’re breaking down the maintenance you can expect from the most common forklift battery type: lead-ion batteries.

How Do You Maintain a Forklift Battery?

For lead-acid batteries (currently the most popular type of forklift batteries by far), there are 4 maintenance procedures to keep top of mind: Watering, Charging/Discharging, Temperature, and General Upkeep. 

1. Watering Your Forklift Battery

As anyone who has thrown a few droplets of water into an oily hot pan knows: oil, water, and heat don’t mix. But that powerful combo is what powers your forklift.

During charging and discharging, evaporation reduces the water levels in your battery. When your acid levels are not properly balanced by water, it causes your battery to run at higher temperatures. Which can quickly do damage to your battery cells.

When water levels in your forklift start dipping below optimal levels, it can also damage your equipment and affect proper functioning — giving you less bang for your battery’s buck.

To properly water your battery:

  • Every 5-10 charges, add deionized or distilled water to your battery. You can check the documents that came with your battery for manufacturer recommendations. Or (and more recommended) keep an eye on your battery’s water levels.

You might also notice a change in your forklift battery’s watering schedule if use of your lift truck becomes more or less frequent.

2. Properly Charging Your Forklift Battery

Are you conventionally charging, fast charging, or opportunity charging? That’s the first thing to know before diving into proper charging care.

Conventional charging is the easiest and most lifetime-extending option for your battery. With conventional charging, you use your battery to power your operations by day, re-charge it in the evening, and cool it down for another day of use by morning.

Fast-charging is occasionally preferred by multi-shift or heavy use operations, though it’s hard on your battery and can quickly degrade the lifespan. With fast-charging, you partially charge the battery in 10-30 minute spurts whenever operators are taking a break.

Opportunity charging is when you take available opportunities — like lunch or break time — to give your battery a little extra juice. Opportunity chargers bring your battery to 80% charge, and help support multi-shift operations.

(For a complete pro/con of conventional charging vs. fast-charging vs. opportunity charging: click here.)

When conventional charging:

  • Discontinue using your forklift battery as soon as it reaches the red zone, which means it has about 20-30% of battery power remaining. This will lengthen your battery’s life while preventing damage to your lift truck.
  • Batteries aren’t “cup half empty” or “cup half full”: they’re all empty or all full. The average battery will support around 1,500 charges in its lifetime. Charging your battery to 50% doesn’t count as half a charge — it counts as a full one. Charging your battery to 100% every time will help you make the most of the charges your battery has in it. 
  • Perform a forklift battery equalization charge weekly. An equalization charge is when you overcharge your battery once a week after it has completed its full charging cycle. Why would you overcharge your battery? To remove unnecessary sulfate build-up and balance the voltage in the cells.

(Many operations choose to perform their forklift battery equalization charge over the weekend, since this process takes more time than a normal charge.)

When opportunity-charging:

  • Charge your battery in the moments when it is not in use. You’ll still want to keep your battery out of the red zone by reaching a minimum of 20% charge at all times. (20-60% of charge is the ideal operation zone when using opportunity charging.)
  • Charge your battery to 100% daily to protect the battery’s health.
  • Perform an equalization charge weekly, just like you would with conventional charging.

3. Care for Your Forklift Battery’s Temperature

Your battery likes it hot. But not too hot. 

When you’re conventionally charging, your ideal battery temperature range is between 60°-100°F.

When you’re opportunity charging, that ideal temperature rises to 60°-125°F.

As soon as you creep past that 100°F mark, you can expect the health of your battery to degrade. Likewise, letting the ambient temperature of your battery dip below 30°F can lead to a performance drop of upwards of 30%.

+ If your lift truck is not in that optimal temperature range, wait to charge until things have cooled down or heated up. + 

Though an over-hot battery might seem to be running without issue in the short-term, excessive temperatures can quickly degrade its performance and require costly maintenance or replacement down the road.

Likewise, a cold battery will be unable to hit its full 100% charge capacity. Which will not only reduce available power in the short-term, but will use up your average 1500 “charging bank” so that your battery dies well before its expected date of replacement.

(Live in California? Want to chat about special circumstances when it comes to your warehouse or needed forklift charging capabilities? Let an expert team know you’re ready to chat about that here.)

4. General Upkeep of Your Forklift Batteries

You can keep to a forklift watering schedule and be fully on top of your lift truck temperatures: but if you’re not taking 5-minutes to do regular battery health checks, you could still be accidentally reducing your battery’s life.

To keep an on-the-ground eye on your forklift battery, use battery cleaner to clean the top of your battery once a month. 

While doing this, take the time to look for the kind of build-up or tray corrosion that can lead to a voided manufacturer warranty and a headache as you seek out a solution.

If you begin to notice any signs your battery should be replaced — like corrosion on the battery case or a rotten egg smell — get in touch with forklift repair and service experts right away.

They’ll be able to help you determine whether your forklift battery needs to be replaced, or whether it simply needs a quick forklift battery maintenance fix.

Quick Questions: We’ve Got Quick Answers

How do you maintain a forklift battery?

Recommended forklift battery maintenance depends on whether your fleet is equipped with lead-acid batteries or lithium-ion. But generally you’ll need to stay aware of proper technique for: watering, charging/discharging, regulating temperature, and staying up with general upkeep. 

How often should forklift batteries be watered?

Forklift batteries need to be watered every 5-10 charges. Check manufacturer recommendations if you’re unsure of frequency, while also knowing that older forklifts are likely to need more frequent watering.

How often should you equalize a forklift battery?

You should equalize a forklift battery weekly. Many operations choose to perform equalizations on the weekend, since it takes longer than a normal charge.

Do you need to use distilled water in forklift batteries?

Yes, you should always use distilled or deionized water for your forklift. Dirt or unseen particulates can easily damage your forklift battery and shorten its lifespan.

Want to expand your forklift battery’s lifespan…while taking regular forklift battery maintenance fully off your plate? Get a team of expert forklift battery technicians to come to your door.)