Battery Basics

Someone read my previous article “Let’s talk about batteries” hoping to learn something about batteries, I mean, the fundamentals of batteries. Instead, he was to complain to me, all he learnt was about 2 battery makers namely CATL and BYD and how they compete against each other for a bigger slice of the pie and how they become so wealthy from batteries. I told him that, despite his misgivings about the article, most people who asked me about batteries are not interested in the technical part of it, but more interested in knowing about the key suppliers, and how prices will be driven down further from the competition. They also want to know enough for their EV purchase consideration and to make sure they make the right decisions for their mobility needs.

Well, we are not calling anyone pedantic (certainly NOT!), we can talk about batteries from a more technical perspective, and to share and exchange knowledge with each other if you may, hence today’s article.

Batteries are highly important in promoting alternative energy, because without the ability to store energy, most of the energy produced can go to waste. Take for instance, solar energy. Without the battery, you can only use solar energy in the day, and only when the sun shines, and hopefully it does not rain…On top of that, most of the solar energy produced goes to waste unless it is immediate consumed.

Battery technology has not changed much in the last 100 years. As I told you before, I used to sell lead acid batteries for a few years, for both motive and stationary power. Motive power refers to power for mobility, so it is used in cars, forklifts, and so on. Stationary power is used for non-mobility purposes, such as your uninterrupted power supply (UPS), even to power the telecom base stations. For motive power, I sold car starter batteries (all types, flooded, AGM, Gel, start-stop etc), deep-cycle batteries, traction batteries. As I said earlier, the technology has remained very stable for decades, unchanged, with innovation mainly in recycling.

Batteries for EVs are different, as EVs require much more powerful batteries. Such batteries have also evolved over time, with the Lithium Ion now being the most widely used. These EV batteries are basically many mobile phone batteries put together to generate more power. Hence, all the issues one encounters with phone batteries apply to EV batteries, though EV batteries have more issues, as there is also battery management system, and protection to prevent explosion from collision, and so on.

Is there any difference between the way lead acid batteries and lithium ion batteries work? The principle is the same, which is the movement of electrons for storage and power release. The main difference between the types of batteries is the material for the electrodes (cathodes and anodes), and the electrolytes. There can be some technological advancements in separators but this is not the most critical component. So battery makers try to develop and enhance batteries by finding material that can help to:

1. reduce cost (cheaper material)
2. reduce weight (lighter material)
3. increase energy density (can store and release more energy)
4. enhance charging cycles (can last longer, deteriorate slower)
5. non-explosive
6. easy to recycle (this will become perhaps the most important issue in the future).

Thus, the continual search for material that can fulfill the above 5 requirements. Lithium ion used to be ideal until the demand soars, and the world soon finds out that supply is limited, and so demand forces drive up costs, so now lithium is getting more and more expensive, and soon it may no longer be commercially viable. Remember, EV makers also have to make sure that EV cost becomes very competitive to internal combustion (ICE) cars. So, CATL is researching sodium batteries, why?

Because sodium is so abundant and cheap. BYD’s blade batteries try to overcome the problem if explosion, but it is expensive to make. Traditional automakers like VW and Toyota are exploring solid state batteries where the electrolyte is not liquid but is solid, hence more compact, non-explosive due to no thermal run away, and potentially more energy dense. E-waste will become a serious issue if lithium ion batteries continue to be expensive to recycle. Note that one of the main reasons why the lead acid batteries can be commercially viable for so long is because 95% of it is recycled.

I told my friend, now that you are armed with the basic knowledge of batteries, you can judge for yourself which battery maker has brighter prospects, and hence higher market value in the near future. He can also decide for himself whether battery leasing is a viable business in the next 5 years. One has to bear in mind that battery costs today is 10% of what it used to be just a decade ago. Had it not been so, Tesla would have been history, imagine that! Finally, he can decide whether his next car should be an EV!
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