Essay: Lithium: Too Hot to Handle or Ship

Aug 7, 2019

You know the drill. Shoes and belts off, laptops out of your bag, 4 ounces or less of liquids. Flying has lost whatever romance it once had.

But what’s the deal with batteries? Why can’t you put them in your checked baggage? Lake Effect essayist Judy Steininger explains:

Lithium. You may not know what it is, but you frequently answer questions about your possession of it. At the post office, the clerk asks if it’s in the package you‘re mailing. At the airport, agents ask if there is any in your checked baggage. You put minute amounts of it next to your ear every time you use your cell phone.

So what is lithium? Why is it important to us; and what makes it so potentially dangerous?

Lithium is an element used in batteries to power everything from cars to cell phones. Lithium has a weight advantage. The more something weighs the more energy is required to power it. A conventional lead/acid battery in the average car weighs approximately forty pounds.

Early cell phones required a carrying case the size of a bowling ball bag. Now, thanks to lithium, we can slip a cell phone into an evening purse or a hip pocket.

Sounds great, right? So why do we get quizzed about shipping or bag checking devices with lithium batteries in them?

Let’s have a brief chemistry lesson. Lithium is one of the 118 elements which alone, or in infinite combinations, form everything in our universe. On the Periodic Table of the Elements, lithium appears on the far left side in a vertical column labeled Group IA. Elements in Group IA: Lithium, Sodium, Potassium, Rubidium, Cesium and Francium, are known as alkali metals; they are highly reactive. In chemistry, reactive means an element undergoes a chemical reaction by itself or with other elements and releases energy. Cesium explodes in water. Gold is very unreactive; hence your ring is made of it.

The alkali metals are highly reactive because each of their atoms has one negatively charged electron positioned far from the nucleus containing the positive protons.  Such elements quickly spin off those electrons to become more stable. Non-metal elements quickly incorporate electrons to make themselves stable. This flow of electrons from the atoms of one element to another can create compounds like salt, it’s chemical formula is NaCl, electricity and energy release, among other things.

Lithium spins off that lone electron so fast it burns at room temperature the instant it is not coated in something thick like mineral oil. Lithium is also the lightest metal in the world and so soft it can be cut with a dull kitchen knife. These characteristics are what make lithium so terrific for batteries: low weight and lots of energy packed in.

So, a tiny cell phone battery contains a positive electrode made of some Lithium oxide; a negative electrode made of a lithium and graphite compound and an electrolyte, another lithium compound through which the electrons flow while the device is either discharging or charging. Electric cars might use different lithium compounds but the principle is the same.

The little chemical factory bonus in your devices is they can have electrons flowing in two directions meaning when one goes dead, just recharge by plugging into a sockets. That forces the electrons to flow in reverse. Nevertheless, treat your Lithium batteries nicely: don’t pound them with a hammer, cut them or overheat. If their seal is broken the lithium is still highly reactive to the air. This is a fire you don’t want to play with.  The battery industry reports the chances of your phone spontaneously exploding is 1 in a million. But now you see the danger is any kind of shipping. The possibility of rough handling or excess heat could cause problems especially in the hold of a plane. In your aisle seat, you would notice and extinguish.

Better, more powerful battery technology is the Holy Grail for our mobile, computerized society. Entire libraries and research facilities exist on this topic. We’ve scarcely touched the surface but now you know why you get quizzed.

Lake Effect essayist Judy Steininger is a Professor Emerita at the Milwaukee School of Engineering, where she leads the Great Books Dinner and Discussion Series.