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Lithium-ion batteries are the most powerful energy storage devices currently available on the market. Their high energy density allows them to achieve superior performance, even with a compact design. That’s why they’re not only used in tablets and digital cameras, but also in the operation of electrically powered industrial trucks. In contrast to other battery technologies, power packs can be recharged at any time, so work can be carried out in multiple shifts.
It’s all made possible by the construction and function of lithium-ion batteries. Ionized lithium atoms move through anhydrous electrolyte or polymer, transferring between a positive electrode made of various metal oxides and a negative electrode made of graphite. A separator, made of nonwoven fibres or polymer films, prevents short circuits. This design, which stores electrical energy through chemical processes, offers many advantages:
- The batteries provide particularly high currents, so even energy-intensive work such as lifting or moving heavy loads is possible.
- Another positive feature is the virtually non-existent memory effect of lithium-ion batteries. Older style batteries continuously lost power due to frequent partial discharging. Lithium batteries, however, have reduced this effect so that capacity remains constant, even during longer periods of operation.
- The overall service life of lithium-ion batteries is also greater when compared to other battery technologies.
The correct way to handle and store lithium-ion batteries
Like any technology, as well as multiple advantages lithium-ion batteries are not without drawbacks. These are primarily concerned with temperature sensitivity. Despite a comparatively low self-discharge of just 1-2% per year, lithium-ion batteries have a tendency to deep discharge when operated at temperatures of less than 5°C and more than 35°C. This can cause irreparable damage. As a result, the vast majority of lithium-ion batteries have integrated controls that effectively prevent deep discharge.
In addition, the installed lithium can be very reactive. In the case of a critically defective battery, overheating can occur as a result of water penetration or even excessive humidity, leading to the risk of fire. An excessively high ambient temperature can also cause instability. As a result, lithium-ion batteries are legally classified as hazardous goods.
Suitable facilities must therefore be available for the transport, storing and charging of lithium-ion batteries, and certain fire safety regulations must be observed. It is also advised to follow current safety recommendations for hazardous material storage.
For example, batteries should only be charged and stored in designated hazardous material cabinets under suitable temperatures. In terms of disposal and recycling of lithium-ion batteries, the relevant regulations must be taken into account.
A large-scale standardized recycling process for lithium-ion batteries, especially for small charge carriers, is not yet available. However, manufacturers and sales outlets, as well as take-back schemes such as INOBAT, BATREC or REMONDIS, offer suitable disposal options for companies that use lithium-ion batteries. When handled correctly, lithium-ion batteries can be used safely and reliably, achieving a long service life of up to 800 charging cycles.
What are the advantages of lithium-ion batteries?
Lithium-ion batteries rank among the most advanced forms of energy storage technology. That’s why they are installed in all kinds of electrically powered devices – from smartphones and battery-powered tools to electric forklifts and e-cars. Advantages include:
- Large current: Large amounts of energy are required, especially for use in devices such as cordless drills or electric stacker trucks. Lithium batteries work well because they provide particularly high amperages. This means they can offer sufficient energy even for energy-intensive operations.
- High energy density: The high energy density of a lithium-ion battery means it can store three to four times as much energy as a nickel-cadmium (NiCd) battery of the same size. This makes them particularly suitable for use in mobile devices, guaranteeing a long service life despite their compact size.
- Low self-discharge: Unlike conventional lead-acid batteries, the self-discharge of lithium-ion batteries is very low, with capacity loss of only 1-2% per month. By storing lithium batteries correctly, this can be maintained even when not in use. However, to safely prevent deep discharge, stored batteries should ideally be recharged once a month.
- No memory effect: The memory effect present in conventional NiCd batteries causes them to lose power over time. Modern lithium-ion batteries work without this memory effect, so that capacity remains constant.
- Intermediate charging is possible: Another advantage of lithium-ion batteries is that they can be intermediately charged at any time, even if the battery is not yet discharged. An intermediate charge can be completed or only partial without damaging the battery.
What are the drawbacks of lithium-ion batteries?
Despite the advanced technology, lithium batteries also have some disadvantages. Many of these drawbacks have already been eliminated or at least improved through technical adjustments. However, some of the downsides are still an issue, including:
- Environmental compatibility and fairness in raw material extraction: The expansion of electromobility, which relies heavily on lithium-ion batteries, is seen as progress in terms of climate and environmental protection. However, the extraction of raw materials for batteries is one of the disadvantages, due to the lack of environmental compatibility and often because of exploitative mining conditions. In particular, the mining or extraction of cobalt, aluminium and lithium can be very damaging to the environment. High water consumption, and pollution from toxic substances washed out in landscapes and ecosystems can also be a major issue. In many mining regions, work also takes place under exploitative conditions, where workers are neither paid fairly nor suitably protected. Nevertheless, compared to conventional lead-acid varieties, lithium-ion batteries are the more environmentally friendly alternative. In addition, some compounds, such as lithium iron phosphate, are less harmful than others and work is underway to optimize mining processes to make them more environmentally friendly.
- Disposal and recycling: Closely related to the issue of the environmental impact of materials is the problem of disposal and recycling. The highly reactive components produce hazardous waste that must be disposed of with appropriate care. Failure to do so can result in dangerous fires and the release of toxic gases into the environment. Due to the combination of different raw materials, the recycling of lithium-ion batteries is a special challenge. There is still no established recycling process for recovering all of the raw materials in a low-pollutant and high-quality manner. Jungheinrich PROFISHOP consultants are happy to answer any questions you may have on this topic.
- Deep discharge: A frequently underestimated disadvantage of lithium polymer batteries is the problem of deep discharge. Completely discharging the battery can cause reverse polarity and other irreparable damage to the lithium cells. To prevent this, good practice must be observed when charging and storing the batteries. However, many modern devices with lithium-ion technology now have integrated controls that protect against deep discharge.
- Temperature sensitivity: Due to the properties of lithium, temperature sensitivity is another disadvantage that affects both the charge level and performance. At low temperatures below 5˚C and at high temperatures above 35˚C, lithium properties can be sensitive. In some cases, deep discharge may even occur. Here, the working and usage environment must be adapted to avoid problems.
Despite the disadvantages of lithium batteries, the benefits of this advanced technology are still significant and more than make up for any shortcomings. Manufacturers and developers are already working on optimising the batteries to make them suitable for widespread use in electric cars. Ultimately, this will also benefit intralogistics vehicles as well as users of mobile devices and power tools. In addition, many of the disadvantages can also be mitigated with the correct storage.
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