What’s the Difference Between Lithium and Lithium-Ion Batteries?

You would be forgiven for thinking they were the same thing. In fact, the confusion about what actually constitutes a lithium-ion as opposed to a lithium battery is such that the vast majority of commentators and battery users alike use the terms interchangeably. This is understandable because there are many similarities between the two and they are indeed both derived from the same technology.

History of Lithium Batteries

Lithium batteries (and lithium-ion) were first developed in the 1990s and have made possible some of the most revolutionary electronic devices that have emerged since that time. Whether it is a laptop or a smartphone, lithium-ion is an essential technology for powering such devices. The advantage lies in their ability to hold significantly more charge and drain considerably slower. Lithium-ion batteries have always made possible the battery management systems and smart batteries that allow electronic devices to report their status, whether that be how much energy is left or how much time is left before the battery needs to be recharged.

And ever since interest in lithium batteries started, research and development of this battery type has never slowed down. Today, lithium batteries have made possible everything from the electric car revolution, which is soon to see our roads filled only with EVs, right down to the small USB-C rechargeable AA smart batteries, being developed by companies like Pale Blue Earth, and bringing the power of lithium-ion rechargeable battery technology into the realm of traditional household batteries.

However, even though this little history of the development of lithium battery technology makes little distinction between the lithium and lithium-ion battery, there is actually a difference. But what is it?

How Lithium and Lithium-Ion Are the Same 

Before tackling that question, it makes sense to first say how lithium and lithium-ion batteries are notdifferent. This is because they resemble each other far more than they don’t. Both types of batteries work by storing charge in a combination of liquid electrolytes. These electrolytes are, in both cases, a lithium salt serving as the positive electrode (anode) and some mixture of ethylene carbonate as the negative (cathode). The way in which both lithium batteries and lithium-ion batteries have been developed has been in refining the precise combinations of these electrolytes, as there are several different chemicals that can make up lithium salt and an ethylene carbonate.

In all cases, this combination and these refinements are precisely that which gives lithium and lithium-ion batteries their desirable qualities, allowing them to hold more charge and deplete slower.

How Lithium and Lithium-Ion Are Different?

Now for the difference – and it is a not-so-subtle one. The real difference, as far as consumers are concerned, is simply that lithium batteries are single-use and lithium-ion batteries are rechargeable. The reason for this is that lithium batteries make use of what is called primary cell construction. The introduction of the “ion” part, on the other hand, means that the battery is composed according to secondary cell construction, thereby making it rechargeable as well as efficient in recharging.

Perhaps the reason why lithium and lithium-ion are terms used so interchangeably is that in the vast majority of cases (or at least the cases we most commonly encounter among today’s technology) lithium-ion batteries are the ones that are used. This is simply because the rechargeable aspect is one of their main advantages.

Nevertheless, the same powerful technology that made everything from the laptop to the electric car possible is present inside both lithium and lithium-ion batteries. They are truly the cornerstone of so much modern technological development – and they’re not going anywhere any time soon.