Handling Lithium Thionyl Chloride Cells

Lithium cells are tremendous sources of electrochemical energy. As such, they are potentially very dangerous if used or handled improperly. Great respect should be given to these cells. Several suggestions which deal with handling lithium cells in a safe and efficient manner follow.

Storage:
Upon receipt cells should be left in the boxes they arrive in right until they are required for use. This will ensure that cells are separated from each other and the chance of an external short circuit occurring is significantly reduced.

Storage areas should be marked with appropriate signage indicating that lithium batteries are located in this area and no water fire extinguishers can be used if a fire occurs. Class D fire extinguishers or powder should be placed in the storage area and also be marked. The storage area should not be located near water tanks, water supply, high humidity areas, or in locations where they may be easily flooded from ceiling leaks or from rain seaping through the floor.

An additional safety precaution would include placing some sodium phosphate powder near by and placing appropriate signage indicating that this is available. The sodium phosphate is helpful should the cell vent or leak and electrolyte leak out as part of the effluent. The electrolyte is quite corrosive and can be neutralized by sodium phosphate.

Material Safety Data Sheets (MSDS) should also be placed in the storage area to provide personnel with information regarding the nature of the commodity being stored.

Ideal temperature range to store cells would be from 0 � 25 C. This will protect the shelf life of the cells and enhance their ability to perform when required. A well ventilated area is also helpful.

Handling:
All contact with cells must be done with non-conductive materials. Any physical measuring required must be done with plastic calipers. Metal calipers may allow a short to be applied to the cell. Open circuit voltage (OCV) tests may be performed with standard voltmeters. Any type of load test can influence the future performance of the battery. It is best if Engineered Power is contacted before these tests are performed.

Additionally, any type of temperature, shock, or vibration tests performed on live cells should be approved by Engineered Power. We have the capacity to perform many of these tests in-house. If we cannot perform the test in-house, we have access to state of the art laboratory facilities to perform various testing at local academic and R&D institutions.

All work surfaces where the cells will be placed should consist of non-conductive materials. Plastic or wood surfaces are best. If cells are being configured into battery packs and the insulating shrink wrap, used to protect cell during shipping, must be removed, care must be taken to prevent the tab from the top of the cell coming into contact with the cell can. The polarity of the tab and can depend on the type of cell. If the positive and negative terminals are allowed to contact, a short circuit occurs and the battery performance will be compromised.

Tabs which extend from the top of the cell are attached to the cell below the visible surface. These tabs are made from very thin metal materials and can easily break or tear if handled roughly. If these tabs do break, the cell is useless. It does not become dangerous. It just cannot be used because it will be missing one of the contact points.

Great care should be taken to avoid allowing the temperature of the cells to increase too much. Soldering directly to the can/case of a cell must be avoided. The solder can create enough heat to turn the lithium into a fluid. Once this happens, the cell has an internal short circuit which is extremely dangerous. Other ways in which the cell temperature may inadvertently be raised would be through external short circuits, wave soldering, or by placing the cell in various potting compounds which cure exothermically. If there are any questions about an activity that you require to perform on a cell, please contact Engineered Power for assistance.