Lithium batteries - opportunity and/or risk

The initial situation

Batteries store electricity electrochemically and thus make electricity available to us on the move. Connected in parallel or in series, batteries enable us to make technical mobile progress.

Quartz wristwatches developed in the early 1970s needed new batteries at the time. Button cells with elemental lithium metal, which reacts violently with water, were developed in the form of non-rechargeable lithium metal batteries. Again, some serious accidents occurred with the introduction of this then-new technology. The introduction of the Walkman in the 1980s called for stronger and, above all, rechargeable batteries. The lithium-ion battery was born - with all its teething troubles such as memory effect, limited charging cycles and great aversion to cold.

And today: For years we have had high-performance batteries in various formats, whether cylindrical, prismatic or pouches (see Wikipedia: Pouch cell). On the cathode side, the lithium cobalt oxide (LCO) has been largely replaced by more efficient lithium manganese oxide spinel (LMS, LMO). The lithium iron phosphate (LFP) cathode, which is far superior in terms of safety and is fireproof in the event of overcharging because it does not contain any oxide as a fire accelerant, has the disadvantage compared with other cathodes that it has low rated voltages with a higher self-discharge. On the anode side, attempts are being made to replace the proven graphite anode with lithium titanate oxide (LTO) or silicon carbon composites (SiC). However, these anode technologies still require optimization in terms of discharge rate as well as expansion during battery charging and also price. Developments are also moving in the direction of using elemental lithium metal, but this again involves the risk of deflagration on contact with water.

In the case of electrolytes that are currently still flammable, the trend is toward solid electrolytes that are no longer flammable and have a longer service life and lower temperature sensitivity.

Shipping regulations

Before shipping lithium-ion batteries or devices containing such power storage devices, the shipper must first identify its batteries. A distinction is made between:

UN 3090 Lithium metal batteries and UN 3091 Lithium metal batteries in and with equipment, and UN 3480 Lithium ion batteries and UN 3481 Lithium ion batteries in and with equipment. Lithium battery powered vehicles are assigned to UN number UN 3171. For the individual UN numbers there are numerous special regulations which can be applied and packing instructions which must be observed.

It can be seen from the following graphs that a well-founded knowledge of the current dangerous goods regulations for the respective mode of transport is important for correct classification.

The most important points before shipping and transporting lithium batteries:

1. Identification of the batteries and devices with such batteries
2. Correct classification according to current dangerous goods regulations, assignment to a UN number
3. Ensuring that a 38.3 certificate is available for the battery to be shipped
4. Check whether special provision 188 can be applied (simplified packaging and labeling, transport by mail permitted).
5. Create process for defective or critical batteries and communicate internally, compliance with respective packaging instructions with higher packaging requirements
6. Create disposal concept for used batteries, never place collection containers in escape routes/stairwells, always keep lid of non-conductive collection container closed, observe information from Inobat (inobat.ch)
7. In instructions for use for devices/vehicles with batteries, draw attention to the dangerous goods regulations to be observed in a practical manner.
8. Appointment of a hazardous materials officer if the type and quantity of batteries requires it

We can look forward to further developments in battery technology and its potential uses. The further development of practical regulations that safely regulate the use, storage, transport and disposal can also be expected.

New VKF leaflet for storage

At the beginning of June, the VKF issued its new leaflet 2005-15 on lithium-ion batteries (cf. here). Lithium-ion batteries are now classified into three hazard levels, as shown in the following table.

The following is recommended for commercial warehouses and logistics operations using lithium-ion batteries:

LIB HL I: No special measures necessary

LIB HL II and HL III:

• Fire compartmentation of the storage rooms with at least fire resistance EI 60, single-storey buildings not used for other purposes can alternatively be built of building materials RF1
• If the total energy content of the LIB exceeds 500 kWh per fire compartment, either small fire compartments with a maximum of 600 m2 each can be formed or an effective sprinkler system specially designed for LIB can be installed in accordance with a recognized standard, e.g. in accordance with VdS CEA 4001 supplemented with VdS 3856
• Installation of a fire-controlled smoke and heat extraction system
• Installation of water extinguishing posts
• Clearance openings to the outside
• Store LIB exclusively in the lower pallet layers of a rack

LIB HL III:

• No storage in high bay warehouse
• Building with lightning protection system
• Pressure relief vents

For used battery collection drums (LIB HL I), the following should be noted:

• Collecting barrels made of building materials RF1 with tightly closing lid and in case of metal barrels make sure that they are lined with a plastic inliner
• Collection points with drop shafts: Design of the discharge chutes and the collection room with at least fire resistance EI 30

The VKF bulletin contains further information on collection points for electrical appliances as well as stationary storage systems of HL I to HL III.

Conclusion

When considered as a whole, the subject seems very complex. To gain clarity, it is worthwhile either attending the relevant course (see box below) or talking to our technical experts.

Author and contact address for professional information:
Ralf Mengwasser, Consultant Integral Safety, Expertise Services - Environmental Safety
T +41 44 877 61 99, ralf.mengwasser@safetycenter.ch
www.safetycenter.ch/gefahrstoff-gut

Matching course: Dangerous goods: storage and transport of lithium batteries https://akademie.svti-gruppe.ch/de/kurse/gefahrgut-lagerung-und-transport-von-lithiumbatterien/k!20348/

Matching meetings:
23rd Dangerous Goods Day Switzerland, 20.10.2021, www.gefahrguttag.ch
10th Hazardous Substances Day Switzerland, 11.11.2021, www.gefahrstofftag.ch