We recently had the opportunity to contribute to an article in Green Manufacturer Magazine titled No-, low-emissions lift trucks clear the air. We contributed to the discussion on electric lift trucks and fast charging applications, but we’ve got more to say on the topic…
How has fast charging enhanced the use of electric-powered forklift trucks?
The fast charging concept was first applied to industrial forklift truck batteries in the 1990s when it was realized that on-road consumer electric vehicles had little to no market potential. Although many users and battery OEMs alike were quite skeptical, extended field trials have demonstrated the viability of fast charging technology and the durability of industrial batteries.
With fast charging, and due to the higher charging rate and the more frequent charging throughout the day, a single battery per truck is needed. This eliminates the need for additional batteries as well as improves truck driver productivity as it eliminates the time wasted in changing batteries in two and three shift applications. In addition, and since a single battery is needed, the battery utilization factor jumps to a full 100% (full utilization of the asset).
Additional savings may be realized from the improved efficiency of fast chargers versus conventional chargers as well as improvement in worker safety as they do not have to move the batteries in and out of the truck on a regular basis.
What types of plants is fast charging best suited for?
Fast charging of industrial batteries is a main stream charging technology due to the operational savings, increased productivity and safety that this technology offers. Users have realized the benefits of fast charging and continue to realize the benefits at manufacturing plants and distribution centers throughout the United States.
What are the best applications for fast charging? What are the limitations of fast charging?
If you operate (plan to operate) battery powered trucks at least 1.5+ shifts per day and do (or anticipate doing) at least one battery change out per day, you may be a candidate for fast charging. The next step is to fully understand the operational profile of the trucks and batteries to discern whether you can actually use fast charging. This can be established through a power study where the battery/truck operation is monitored throughout the week. For the collected data, one can establish whether there are adequate opportunities for fast charging through the shift or day as well as a weekly opportunity to perform a finish / equalize cycle.
- Charging rates of 25A/100 Ahrs
- 4-6 hour charge intervals (1.5+ shift applications)
- 100% daily recharge
- Charging rates of 40+A/100Ahrs
- 2-4 hour charge intervals (1.5-2+ shift applications)
- Charge during breaks, lunches, and at the end of shifts
- Common to recharge from 30-80% state of charge (SOC) in 1-2 hour intervals
- 80-85% daily recharge; 100% recharge once per week
- Requires battery modifications and accessories
- Allows operations to run on 1 battery per truck
- Eliminates battery changing
- Battery utilization: 100%
For more on the topic, read one or both of our featured whitepapers.