I have been working on some personal research on electric vehicles over this last week and discovered a few major issues that prevent us from reaching the current government goal of 50 percent of all new vehicles being electric by 2025. The first is the lack of safe, stable, recyclable and inexpensive rechargeable batteries. Just a quick look into battery technology and you quickly discover the issues. There are four main chemical types in rechargeable batteries: lithium batteries, lead acid batteries, nickel cadmium and nickel iron. Each of these main types have different pros and cons for use in electric vehicles.Lithium based batteries have become the industry standard in nearly all electronics, but are actually quite dangerous. It does not take long to find internet videos of lithium battery fires. There are two main ways the battery can fail, resulting in fire, and both can occur fairly easily. The first is through an electric short circuit; this usually occurs during charging with a failed charge cord. A short circuit means that the battery has a direct connection between the positive and negative terminals, allowing maximum current to flow, generating extreme heat and eventually fire. The second is through physical damage to the battery. A great example would be dropping your cellphone; if it lands in such a manner that the battery is bent or punctured, it can catch on fire. The fire is not the worst part – lithium fires have two main problems, lithium reacts violently with water and the smoke from a lithium fire is extremely toxic and known to cause blindness. Imagine for a moment that you are involved in a car accident with an electric vehicle that catches on fire, you are trapped near the smoke, and even though you survived the accident, you spend the rest of your life blind. Not my idea of a safe battery.Lead acid batteries are relatively safe compared to lithium, but also extremely heavy and much less efficient when it comes to energy density. To give you an idea of what I mean, I recently replaced my solar battery bank at my house. I decided to go with the lead acid batteries because of cost over time, but I could have purchased four lithium batteries at 100 pounds each instead of 16 lead acid batteries at 125 pounds each, nearly 20 times more weight in the lead acid over the lithium. If your cell phone used lead acid batteries it would weigh around 20 pounds. Nickel cadmium batteries are comparable in weight and power density to the lithium batteries and nearly as safe as the lead acid batteries, but they have a different problem. Nickel cadmium batteries acquire a memory. What this means is if they are not completely discharged between charging cycles, they will begin to hold less charge. This is a real problem for most rechargeable battery applications. They work okay for battery powered toys and tools, but not for critical systems like the solar power bank for your home, which incidentally is constantly charging when the sun is shining. These batteries would fail in a solar bank in a matter of months. If you want to see this for yourself, buy a cheap solar lamp. They usually have nickel cadmium batteries. You will notice that, when it is new, it will stay on most of the night, but after about three months it goes out around midnight, and after six months you will be lucky to see it light up at all. My favorite is the nickel iron battery; in terms of safety and longevity it takes the lead. Thomas Edison built the first nickel iron batteries and they were used in the early telegraph systems. There are still a few of Edison’s original batteries in operation today, over two hundred years later. The chemical reaction allowing the charge and discharge improves with repeated use; all other batteries get worse the longer they are used. They use a base instead of an acid in the chemical reaction. In fact, all three components are safe both separately and when combined in the battery. The base is commonly found in laundry soap. So why not use this safe battery with no rare earth metals and common safe chemicals? The main reason is the weight; they come in nearly two times heavier than lead acid. A nickel iron battery in your cell phone would weigh in at nearly 40 pounds.Next week I will talk about another factor blocking widespread use of electric vehicles. Until next week stay safe and learn something new.Scott Hamilton is an Expert in Emerging Technologies at ATOS and can be reached with questions and comments via email to shamilton@techshepherd.org or through his website at https://www.techshepherd.org.

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