Efficiently testing and preparing drive batteries
Electrically powered industrial trucks, such as forklifts or pickers, mainly use lead- acid batteries as energy storage today. With good care and proper use these batteries have a very long service life of about 1,000 to 1,500 charge cycles.
Given the investment cost of approximately € 3,500 for an average lead-acid traction battery it is necessary to utilise this resource optimally. BENNING has developed a solution that does precisely this.
Companies that specialise in the rental or lease of traction batteries often have hun- dreds or even thousands of batteries in the field. Their service life and knowledge of the condition of respective batteries therefore contribute significantly to the success of this business model. Therefore, the evaluation of a battery is a key issue, especially in the rental business. Many batteries return from the rental business after several years of op- eration and some can still provide good, long service as used batteries.
Battery reconditioning makes sense
There are a number of applications where new batteries are not required, and recondi- tioned batteries are sufficient. This applies to areas in which the batteries are only slightly used. For example, the occasional loading and unloading of trucks. Here refurbished, used batteries can still be used for many years. After all, they are usually considerably cheaper both to purchase and rent. In addi- tion, reconditioning batteries also makes sense from a resource conservation point of view.
Condition not visible from the outside
In practice, therefore, the question of the ac- tual condition of batteries in the field or of re- turning batteries often arises. Unfortunately, from the outside it is not clear how many charge cycles are still available – a “simple laying on of hands” cannot be carried out as with the measurement of acid density and cell voltage. These measurements are cer- tainly sufficient for a rough assessment, but a qualified statement about the remaining service life is not possible.
The solution is the ‘capacity test’. In this case the battery is first charged and then with a defined current completely discharges to the cut-off voltage. Taking into account some constraint, the remaining capacity can then be determined using this method.
Qualified statements for practice
For the applied testing method, which is de- scribed in detail in accordance with DIN, BEN- NING has manufactured special battery forma- tion and test systems (BFS 2000) for many years. These converters enable reliable testing and can be used for formation processes re- quired in battery production and also for the serial testing of new and used batteries.
Sustainable use of energy
The systems work as charging and discharg- ing equipment in a unit. In a charging process energy is extracted from the grid and fed into the battery in a controlled way. To ensure that the power extracted during discharge of the batteries is not unnecessarily converted into heat, the BENNING BFS 2000 systems work as reversible converters with regenerative feedback.
The extracted energy is stored in the in- house grid and as a result power supplies can be used to efficiently supply other loads. In this way the BFS 2000 helps the operator save energy and costs. With regular use, therefore, e.g. in battery reprocessing, the re- generative power unit also makes sense from an environmental point of view.
Documentation as proof of quality
The BSF 2000 is easy to use in practice, as all formation and testing operations are con- trolled by software, which records and saves readings.
For protocols, all data is electronically avail- able and can then be further processed and transferred into in-house documentation, for example. This detailed representation of the battery status, including the measured data and protocols, serves as qualified proof of the used battery’s current status.
“The key feature of the BFS 2000 is efficient power regeneration through discharge. There are systems on the market that are constructed much more simply and merely convert energy into heat during discharge. This does not make sense from a cost and environmental point of view.”
contact: Peter Hoeptner
telephone: +49 (0) 28 71 / 93-233