{"id":246,"date":"2017-01-30T20:58:47","date_gmt":"2017-01-31T01:58:47","guid":{"rendered":"http:\/\/www.circuitcrush.com\/?p=246"},"modified":"2021-06-30T21:36:40","modified_gmt":"2021-07-01T01:36:40","slug":"battery-types-how-they-work-1","status":"publish","type":"post","link":"https:\/\/www.circuitcrush.com\/battery-types-how-they-work-1\/","title":{"rendered":"Types of Batteries & How They Work Part 1"},"content":{"rendered":"<p>There are many different types of batteries, and they are an invention that, believe it or not, dates back several thousand years.<\/p>\n<p>What appears to be ancient batteries have been unearthed in what is now Iraq. These batteries were made of clay jars filled with vinegar. An iron rod surrounded by a copper cylinder was placed in the vinegar. These ancient cells typically produced 1-2 volts.<\/p>\n<p>What ancient Iraqis would have done with 2V remains somewhat of a mystery, but the invention of the first \u201creal\u201d battery is credited to Alessandro Volta around 1800.<\/p>\n<p>Why Volta and the not ancient Iraqis?<\/p>\n<p>For one, no one knows who the original designer of the ancient battery was.<\/p>\n<p>Secondly, it\u2019s likely that Volta had at least some rudimentary understanding of how his battery worked, while no one\u2019s sure if the ancient Iraqis did or if they even used it as a battery at all. The verdict on what exactly this artifact was intended for is still out.<\/p>\n<p>Of course, Volta\u2019s battery (and the ancient versions) were nothing like the batteries you\u2019re used to working with today.<\/p>\n<p><!--more--><\/p>\n<h1><strong>How Batteries Work<\/strong><\/h1>\n<p>A modern-day battery consists of two separated dissimilar metals within an electrolyte. The whole package is enclosed in a container, usually either metal or plastic.<\/p>\n<p>The electrolyte is usually an acid and causes a chemical reaction that pushes electrons from on plate or rod, through the electrolyte, to the opposite plate or rod. In other words, the reaction causes electrons to pass through the electrolyte as they are repelled from one plate and attracted to the other.<\/p>\n<p>The rods\/plates are the battery’s electrodes. One electrode is the anode and the other the cathode. When discharging, the anode is negative and the cathode positive. When charging a rechargeable battery, it\u2019s the opposite.<\/p>\n<p>The electrons are held in the negative electrode when nothing\u2019s connected to the battery.<\/p>\n<p>But, when something conductive, like an LED is place across its terminals the electrons flow through the circuit and do useful work.<\/p>\n<p>Note that directly shorting the terminals of a battery can be dangerous, especially on larger batteries.<\/p>\n<p>Real batteries have a finite shelf life and will eventually self-discharge even if never used.<\/p>\n<h1><strong>Connecting Batteries Together<br \/>\n<\/strong><\/h1>\n<p>The way in which you connect batteries together (if you need more than one) depends on the needs of the device they’re powering.<\/p>\n<p>Batteries in series will have voltages that will add up, so if you need more than 1.5 V this may be the way to go. The downside to this is that the total Ah capacity of the pack is equal to the capacity of one individual battery.<\/p>\n<p>A group of batteries wired in parallel will produce more current. The voltage of the whole group of batteries will be the same as the voltage of any individual battery.<\/p>\n<p>If you are concerned about wringing more amp-hours out of your batteries, this maybe the way to go. The total current (or Ah) that flows is the current (Ah) capability of any individual battery multiplied by the number of batteries in the group.<\/p>\n<p>The figure below (borrowed from howstuffworks.com) illustrates this.<\/p>\n<p><img fetchpriority=\"high\" decoding=\"async\" class=\"aligncenter size-full wp-image-247\" src=\"http:\/\/www.circuitcrush.com\/wp-content\/uploads\/batteries-wired.gif\" alt=\"Batteries can be wired in series or parallel\" width=\"400\" height=\"394\" srcset=\"https:\/\/www.circuitcrush.com\/wp-content\/uploads\/batteries-wired.gif 400w, https:\/\/www.circuitcrush.com\/wp-content\/uploads\/batteries-wired-100x100.gif 100w\" sizes=\"(max-width: 400px) 100vw, 400px\" \/><\/p>\n<p> <\/p>\n<h1><strong>Battery Capacity<\/strong><\/h1>\n<p>The amp-hour (Ah) is the unit of measure for battery capacity (<em>C)<\/em>.<\/p>\n<p>Recall that Coulombs are the unit of measure for charge (<em>Q<\/em>) and that one Coulomb is equal to the charge transferred in 1 second by 1 Amp of current. Put another way, 1 A = 1 Coulomb per 1 second. This simplifies to A (current) = Q (charge) divided by t (time in seconds). Therefore, current is equal to the amount of charge transferred per second. One Coulomb of charge contains 6.24 x <sup>18 <\/sup>electrons.<\/p>\n<p>Confused? The example below may help.<\/p>\n<p><strong><u>Ex. 1<\/u><\/strong><\/p>\n<p>Suppose 5 x 10<sup>19 <\/sup>electrons pass a point in a conductor in 2 seconds. How much current is that?<\/p>\n<p>To figure this out, we first need to see how many Coulombs 5 x 10<sup>19 <\/sup>electrons is: (5 x 10<sup>19<\/sup>) \/ (6.24 x 10<sup>18<\/sup>) = 8 Coulombs.<\/p>\n<p>Now, we simply divide the number of Coulombs by the time in seconds: Q\/s = 8\/2 = 4 A.<\/p>\n<p>One Amp-hour is equal to 3600 Coulombs. This is because there are 3600 seconds in one hour.<\/p>\n<p>From a practical standpoint, you likely won\u2019t be counting electrons or measuring Coulombs.<\/p>\n<p>So why all the fuss then?<\/p>\n<p>As we said before, battery capacity is measured in Ah, and, as we\u2019ve seen these lower-level units make up the Ah. The amp-hour is a unit that you may need to work with when designing things that run on batteries. Many of you may be familiar with the unit and what it actually means, but some of you may not, so I thought I\u2019d peel back the layers for a moment.<\/p>\n<p>Anyway, if I have a 20 Ah battery, it can supply 20 A for one hour or 10 A for 2 hours or 2 A for 10 hours and so on.<\/p>\n<p>Here\u2019s an example that can help you calculate the battery capacity you\u2019ll need for a given project:<\/p>\n<p><strong><u>Ex. 2<\/u><\/strong><\/p>\n<p>Say you want to use a 300 Ah battery for your project and you know that your widget will draw 3 A. How many hours can you run your device before the battery dies?<\/p>\n<p>All we need to do is divide the battery capacity by the amount of current your creation draws:<\/p>\n<p>300 Ah\/3 A = 100 hours of run time.<\/p>\n<h1>The 2 Types of Batteries<\/h1>\n<p>There are two main types of batteries: primary and secondary cells.<\/p>\n<h3 style=\"text-align: center;\">Become the Maker you were born to be. Try <a href=\"https:\/\/learnarduinonow.com\">Arduino Academy<\/a> for FREE!<\/h3>\n<p><img decoding=\"async\" class=\"aligncenter wp-image-4238\" src=\"https:\/\/www.circuitcrush.com\/wp-content\/uploads\/FB_Cover2.png\" alt=\"\" width=\"504\" height=\"192\" srcset=\"https:\/\/www.circuitcrush.com\/wp-content\/uploads\/FB_Cover2.png 828w, https:\/\/www.circuitcrush.com\/wp-content\/uploads\/FB_Cover2-300x114.png 300w, https:\/\/www.circuitcrush.com\/wp-content\/uploads\/FB_Cover2-150x57.png 150w, https:\/\/www.circuitcrush.com\/wp-content\/uploads\/FB_Cover2-768x292.png 768w\" sizes=\"(max-width: 504px) 100vw, 504px\" \/><\/p>\n<p>Secondary cells are rechargeable, primary cells are not.<\/p>\n<p>Because of space limitations, this post discusses primary cells from here on. A future post will go into secondary cells and their types and uses.<\/p>\n<p>The type you end up picking will depend on the project.<\/p>\n<p>We\u2019re all familiar with D, C, AA, AAA and 9 V batteries that are cheap and readily available at most stores. These are examples of primary cells.<\/p>\n<p>Some other types of primary batteries include button or coin cells, A23, 123 and others.<\/p>\n<h1><strong>Primary Battery Cell Chemistry<\/strong><\/h1>\n<p>The chemical reaction\u00a0 within a primary cell eventually dissolves the negative plate. Also, hydrogen gas bubbles form around the positive plate, causing a resistance between the two plates. This is known as the battery\u2019s internal resistance. The addition of a depolarizer slows down the buildup of hydrogen gas bubbles, but with time the battery\u2019s resistance still will increase as it discharges.<\/p>\n<p>If you\u2019re using a common battery size (such as AA or 9 V), you\u2019re likely using one of three different chemistries: carbon-zinc, alkaline, or lithium.<\/p>\n<h3><strong>Carbon-zinc batteries<\/strong><\/h3>\n<p>These are the least expensive with a long shelf-life, but have the lowest capacity. They are good for low-drain devices like clocks, radios, and your TV remote. This is the original chemistry for batteries, dating back to the 1800s. The anode is zinc, the cathode is manganese dioxide, and the electrolyte is ammonium chloride or zinc chloride. The cathode contains powdered carbon to improve conductivity and for moisture retention.<\/p>\n<h3><strong>Alkaline batteries<\/strong><\/h3>\n<p>These have an even better shelf life and can last anywhere from 2-10x longer than carbon-zinc batteries (depending on the application), with only a small additional cost. This is why most household batteries today are of this type.<\/p>\n<p>The cons are that standard alkalines don\u2019t perform well in high-drain devices because they can’t supply current fast enough. More expensive, specialized alkaline batteries that perform a bit better in high-drain devices are available, but in cases like this you might as well use a rechargeable battery. They are also more prone to leaking and thus damaging electronics than carbon-zinc or lithium. Here are a few things you can do to reduce the likelihood of a leak.<\/p>\n<ul>\n<li>Do not try to recharge an alkaline battery<\/li>\n<li>Don\u2019t mix fresh batteries with used ones<\/li>\n<li>Don\u2019t mix alkaline batteries with other types<\/li>\n<li>Long exposure to high temperatures can cause leaking<\/li>\n<li>Don\u2019t let dead batteries sit around inside your device<\/li>\n<\/ul>\n<p>The cathode is composed of a manganese dioxide mixture, while the anode is a zinc powder. Alkaline batteries get their name from the potassium hydroxide electrolyte, which is an alkaline substance.<\/p>\n<h3>Lithium Batteries<\/h3>\n<p>Do not confuse Lithium batteries with lithium ion batteries, which are rechargeable.<\/p>\n<p>Unlike carbon-zinc and alkaline batteries, lithium batteries work great in high-drain devices. They also boast the longest shelf life of the group, are light weight, and can operate in extreme temperatures ranging from -40 C up to +60 C.<\/p>\n<p>The few cons are that they are the most expensive of the group and there is a small risk of explosion. Because of this risk you cannot send lithium batteries in the U.S. mail, nor can you check them with your baggage when flying.<\/p>\n<p>One common type of Lithium battery uses lithium for the anode, iron disulfide for the cathode, and a lithium salt in an organic solvent blend as the electrolyte. However, per the <a href=\"http:\/\/data.energizer.com\/pdfs\/lithiuml91l92_appman.pdf\">Energizer PDF<\/a> on lithium batteries, there are several different types of chemistries.<\/p>\n<p>The document states that the term \u201clithium battery\u201d refers to many different chemistries utilizing lithium as the anode\u00a0 but\u00a0 differing\u00a0 in\u00a0 cathode\u00a0 material,\u00a0 electrolyte,\u00a0 and\u00a0 construction.\u00a0 They\u00a0 may\u00a0 be classified\u00a0 in\u00a0 several\u00a0 ways, but\u00a0 one\u00a0 convenient\u00a0 method\u00a0 is\u00a0 by\u00a0 the\u00a0 cathode\u00a0 material\u00a0 and voltage.\u00a0 Using\u00a0 an\u00a0 iron\u00a0 disulfide\u00a0 cathode\u00a0 gives\u00a0 a\u00a0 battery\u00a0 with\u00a0 a\u00a0 nominal\u00a0 voltage\u00a0 of\u00a0 1.5 volts.\u00a0 Most other lithium batteries are 3.0 volt systems using cathodes comprising either solids (manganese dioxide or carbon monofluoride) or highly toxic liquids (sulfur dioxide or thionyl chloride).<\/p>\n<p>The chart below, taken from one of my old text books, summarizes most of the common types of batteries nicely. For some reason the chart does not include 1.5 V lithium batteries, but it does include lithium button cells.<\/p>\n<p><img decoding=\"async\" class=\"aligncenter size-full wp-image-248\" src=\"http:\/\/www.circuitcrush.com\/wp-content\/uploads\/Battery-Types.jpg\" alt=\"Types of batteries\" width=\"707\" height=\"669\" srcset=\"https:\/\/www.circuitcrush.com\/wp-content\/uploads\/Battery-Types.jpg 707w, https:\/\/www.circuitcrush.com\/wp-content\/uploads\/Battery-Types-600x568.jpg 600w, https:\/\/www.circuitcrush.com\/wp-content\/uploads\/Battery-Types-150x142.jpg 150w, https:\/\/www.circuitcrush.com\/wp-content\/uploads\/Battery-Types-300x284.jpg 300w\" sizes=\"(max-width: 707px) 100vw, 707px\" \/><\/p>\n<p> <\/p>\n<p>Now we got some basic battery theory down and know more about common types primary cells. As I mentioned before, part two of this series will delve into types of secondary (rechargeable) batteries.<\/p>\n<p>Stay tuned!<\/p>\n<p><em><strong>Update: part 2 about <a href=\"http:\/\/www.circuitcrush.com\/types-of-batteries-rechargeables\/\" target=\"_blank\" rel=\"noopener noreferrer\">rechargeable batteries<\/a> is here!<\/strong><\/em><\/p>\n<h2 style=\"text-align: center;\">Become the Maker you were born to be. Try <a href=\"https:\/\/learnarduinonow.com\">Arduino Academy<\/a> for FREE!<\/h2>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter size-full wp-image-4238\" src=\"https:\/\/www.circuitcrush.com\/wp-content\/uploads\/FB_Cover2.png\" alt=\"\" width=\"828\" height=\"315\" srcset=\"https:\/\/www.circuitcrush.com\/wp-content\/uploads\/FB_Cover2.png 828w, https:\/\/www.circuitcrush.com\/wp-content\/uploads\/FB_Cover2-300x114.png 300w, https:\/\/www.circuitcrush.com\/wp-content\/uploads\/FB_Cover2-150x57.png 150w, https:\/\/www.circuitcrush.com\/wp-content\/uploads\/FB_Cover2-768x292.png 768w\" sizes=\"(max-width: 828px) 100vw, 828px\" \/><\/p>\n<a target=\"_blank\" href=\"https:\/\/www.drpeterscode.com\/index.php\"><img src=\"https:\/\/www.circuitcrush.com\/wp-content\/plugins\/dpabottomofpostpage\/apixel1x1.jpg\" ><\/a><table><\/table>","protected":false},"excerpt":{"rendered":"<p>There are many different types of batteries, and they are an invention that, believe it or not, dates back several thousand years. What appears to be ancient batteries have been unearthed in what is now Iraq. These batteries were made of clay jars filled with vinegar. An iron rod surrounded by a copper cylinder was […]<\/p>\n","protected":false},"author":1,"featured_media":255,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_genesis_hide_title":false,"_genesis_hide_breadcrumbs":false,"_genesis_hide_singular_image":false,"_genesis_hide_footer_widgets":false,"_genesis_custom_body_class":"","_genesis_custom_post_class":"","_genesis_layout":"","_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[38,9],"tags":[39,40,42,43,41],"class_list":{"0":"post-246","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-batteries","8":"category-electronics","9":"tag-batteries","10":"tag-battery","11":"tag-battery-types","12":"tag-how-batteries-work","13":"tag-primary-battery","14":"entry"},"jetpack_sharing_enabled":true,"jetpack_featured_media_url":"https:\/\/www.circuitcrush.com\/wp-content\/uploads\/Batteries.jpg","_links":{"self":[{"href":"https:\/\/www.circuitcrush.com\/wp-json\/wp\/v2\/posts\/246","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.circuitcrush.com\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.circuitcrush.com\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.circuitcrush.com\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.circuitcrush.com\/wp-json\/wp\/v2\/comments?post=246"}],"version-history":[{"count":2,"href":"https:\/\/www.circuitcrush.com\/wp-json\/wp\/v2\/posts\/246\/revisions"}],"predecessor-version":[{"id":4356,"href":"https:\/\/www.circuitcrush.com\/wp-json\/wp\/v2\/posts\/246\/revisions\/4356"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.circuitcrush.com\/wp-json\/wp\/v2\/media\/255"}],"wp:attachment":[{"href":"https:\/\/www.circuitcrush.com\/wp-json\/wp\/v2\/media?parent=246"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.circuitcrush.com\/wp-json\/wp\/v2\/categories?post=246"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.circuitcrush.com\/wp-json\/wp\/v2\/tags?post=246"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}