How to store lithium-ion-batteries: tips for service life & fire protection
As a specialist in battery storage boxes, we are regularly asked for tips on how to store lithium-ion batteries. On the one hand, this involves careful storage to preserve the service life. On the other hand, this also includes fire protection during storage. The latter does not only apply to damaged and bloated batteries, but is particularly critical for these.
Gentle battery storage to preserve the service life
The optimum storage conditions for a lithium-ion battery can vary in detail from model to model. Therefore, when storing rechargeable batteries, the manufacturer's instructions, which can be found in the user manual, should be carefully observed. In general, it can be assumed that rechargeable batteries have a long service life if they are stored under the following conditions:
- Lithium-ion-batteries should not be stored too warm or too cold. The permissible temperatures can be found in the operating instructions. As a rule, it is advisable to store batteries at room temperature and to avoid frost in particular. Heat sources like direct sunlight should also be avoided.
- If batteries are stored, they should neither be fully charged nor (almost) empty. Ideally, batteries should be stored at a medium charge level. If the charge is too low, a deep discharge can occur during storage, which can damage the battery. On the other hand, the slightly higher voltage of a fully charged battery can lead to accelerated ageing. The charge status should be checked every few weeks during long periods of storage.
- Batteries should also be stored in a clean and dry place. Dirt and moisture can not only lead to corrosion on the housing and contacts, but can also cause leakage currents. Leakage currents consume energy, which can even lead to deep discharge. Attention should also be paid to condensation, which can occur when temperatures fluctuate, for example.
- When storing devices with rechargeable batteries, the batteries should be removed or disconnected. Most electrical devices still consume some power even when switched off, which can also lead to deep discharge.
Fire protection for stored lithium-ion-batteries
The topic of fire protection for lithium-ion batteries is also relevant in private households, for example for e-bike batteries. We have developed our RETRON BOX especially for this purpose. The issue of fire protection becomes critical when storing lithium-ion-batteries in industry and other trades such as retail or logistics. Due to the large quantities of stored batteries, a chain reaction and non-extinguishable fires can occur here.
The conditions under which large quantities of lithium-ion batteries and other batteries are stored should therefore be checked with your own fire insurance company – for example based on VDS 3103 – and with the local fire service. It may also make sense to consult your own fire protection expert. Here are some tips that are generally recommended:
- The above-mentioned measures for a long service life are also beneficial for fire protection. For example, deep discharging increases the risk of a fire, while a fully charged battery can release more energy in the event of a fire, thus fuelling the fire.
- If the batteries are delivered still packaged, they should be stored in the packaging for as long as possible. This protects the batteries from moisture, dirt, damage and short circuits, among other things.
- As the risk of fire is greatest during charging, the batteries should not be charged where large quantities of batteries and lithium-ion batteries (or other flammable materials) are stored.
- The spread of fire from one battery to other stored batteries or other easily flammable objects poses a major risk. For this reason, large quantities of lithium-ion batteries should not be stored together or together with other flammable materials, but should be stored separately. Conversely, of course, no potential sources of fire should be stored next to lithium-ion batteries. If separation by firewalls is not possible,fireproof battery containers such as those we offer can also be used.
When storing lithium-ion-batteries, other fire protection measures such as sprinkler systems, fire doors and smoke extraction should also be adapted to the particular dangers of burning batteries. Although sprinklers cannot usually extinguish a burning battery, they can often prevent the flames from spreading until the battery has burnt out. In the case of burning batteries, very rapid smoke development must also be expected, as flames and smoke usually emerge from the stored lithium battery at high pressure.
Storing damaged and inflated lithium-ion-batteries
Damaged batteries are considered to be particularly dangerous, as the damage can cause short circuits and, as a result, ‘thermal runaway’. This also applies to inflated batteries. The risk is considered to be so high that damaged or inflated batteries may only be transported under strict safety precautions in accordance with the ADR special provisions.
Special safety measures should therefore also be taken when storing damaged and swollen batteries. We recommend storage in a special safety container and rapid disposal of the damaged batteries. RETRON not only provides the necessary containers but also works with REMONDIS to ensure that the batteries are disposed of safely.
Do you still have questions about storing batteries in the commercial sector? Please do not hesitate to contact us!
