Electric forklifts that rely on electric motors and industrial batteries are growing in popularity and are offered by many forklift manufacturers. Recent improvements and advancements in technology have allowed them to compete directly with their internal combustion counterparts but with lower operating and maintenance costs, fewer emissions and quieter operation.
Within electric forklifts, you’ll find some that run on lead-acid batteries and others that use the lithium-ion variety. (And within lithium-ion batteries, there are different types of battery chemistries that can affect performance on certain metrics.)
Lead-acid batteries have been around for more than 150 years. You may be familiar with them from their use as the 12-volt battery in your car. Lithium-ion batteries were introduced more recently but are now used in many consumer electronics and in electric vehicles.
All battery chemistries include tradeoffs. One might require more maintenance but be cheaper upfront. Another might excel in energy density — how much energy it can pack in — but have a weaker cycle life, or how many sessions of charging and discharging it can achieve.
Here’s how lead-acid and lithium-ion batteries compare on measures important in the material handling world.
The biggest advantage for lead-acid batteries is their cost. They can be substantially cheaper than similar lithium-ion batteries, though the price of the latter has been coming down.
Maintenance and Safety
One large drawback to lead-acid batteries is the maintenance they need. Because of their battery chemistry, they must be regularly watered, cleaned and equalized, which costs valuable time and money. Lithium-ion batteries, on the other hand, require practically zero maintenance — there’s no fluid or equalizing to worry about. They are also safer than lead-acid batteries, and the lithium iron phosphate battery chemistry in particular is known for its safety characteristics.
Lead-acid batteries require strict charging conditions and longer charge times. They are often swapped during shifts to get a fresh battery at the start while charging a used one. Lithium-ion batteries can charge more quickly and in brief periods throughout the day, meaning you can get back to work without delay. They also don’t require battery swapping, need to be removed from forklifts to charge or demand a specific battery room.
Lithium-ion batteries can perform consistently throughout a shift, unlike lead-acid batteries, which tend to weaken in performance as they lose charge.
Lithium-ion batteries should last more cycles than lead-acid batteries — about twice as many — before needing to be replaced. However, keep in mind that if you use multiple lead-acid batteries and swap them at shift changes, each battery will go through fewer cycles over a given period, as you are splitting the workload across batteries.
Lithium-ion batteries surpass lead-acid batteries on many measures, except for a big one: initial cost. It’s important to do your research to see how the factors stack up for your operation.FeatureLead-AcidLithium-Ion Upfront Cost + – Maintenance and Safety – + Charging – + Performance – + Service Life – +