{"id":947,"date":"2008-07-30T15:54:41","date_gmt":"2008-07-30T19:54:41","guid":{"rendered":"http:\/\/blogs.n1zyy.com\/n1zyy\/?p=947"},"modified":"2008-07-30T15:54:41","modified_gmt":"2008-07-30T19:54:41","slug":"unreasonably-much-information-about-batteries","status":"publish","type":"post","link":"https:\/\/blogs.n1zyy.com\/n1zyy\/2008\/07\/30\/unreasonably-much-information-about-batteries\/","title":{"rendered":"Unreasonably Much Information about Batteries"},"content":{"rendered":"<p>A few things I&#8217;ve learned about batteries lately:<\/p>\n<ul>\n    <li>Rechargeable AA&#8217;s are 1.2V, whereas normal alkaline AA&#8217;s are 1.5V. I didn&#8217;t believe this at first, but it&#8217;s usually printed right on the battery (in unreasonably small print). Where this generally matters is things that take many batteries (in my radio that takes 4, it&#8217;s the difference between 4.8V and 6V, for example), although <em>most<\/em> things will work just fine. (The rechargeables often have much higher capacities, though, so it works out&#8230; Unless you get something that&#8217;s very nitpicky about voltage.)<\/li>\n    <li>Almost all &#8220;normal&#8221; alkaline batteries: AA&#8217;s, AAA&#8217;s, C&#8217;s, and D&#8217;s, are 1.5V. The typical capacity of a AA is somewhere around 1,000-2,000 mAh, but did you know D-cells are often around 15,000 mAh? (Which is 15 Amps if I&#8217;m not mistaken, which means it&#8217;s got about 25WH of juice.)<\/li>\n    <li>As a consequence of the above, as far as voltage is concerned, you can use a AAA where a D is called for, or a D where a AA is called for, and they&#8217;re all the same voltage. It&#8217;s just that, as the batteries get bigger, they last a lot longer. (And good luck sticking four D-cells into your camera so it last longer&#8230;)<\/li>\n    <li>&#8220;Digital&#8221; devices will stop working below a certain voltage, which is usually before the battery is fully drained. Unlike a flashlight, which will just get dimmer and dimmer as the battery drains, electronics (think of cameras, for example) will continue working until there&#8217;s insufficient voltage, at which point they shut down. Thus the &#8220;dead&#8221; batteries from a camera (etc.) may continue to work in other things, like a remote control or a flashlight, though the flashlight would, of course, be dimmer than usual, since the batteries you put in would be low.<\/li>\n    <li><a href=\"http:\/\/the-gadgeteer.com\/review\/battery_xtender_alkaline_battery_recharger\">It&#8217;s possible to recharge alkaline batteries<\/a> if they&#8217;re not <em>completely<\/em> flat. But <strong>don&#8217;t try this at home<\/strong> (unless you have the aforementioned charger or a desire to have boiling battery acid in your eyes): alkaline batteries were never meant to be recharged, so ordinary battery chargers will cause the batteries to overheat, ooze acid, or just flat-out blow up. But if you get a charger specially designed to recharge non-rechargeable batteries, it can be done!<\/li>\n    <li><a href=\"http:\/\/en.wikipedia.org\/wiki\/AAAA_battery\">There&#8217;s a AAAA battery<\/a>, and it&#8217;s exactly what you think it is. The AAA is a smaller version of the AA, and consequentially doesn&#8217;t hold as much of a charge; the AAAA, then, is a smaller AAA which holds less of a charge. You probably haven&#8217;t seen many AAAAs, but that doesn&#8217;t mean they&#8217;re rare. That&#8217;s because&#8230;<\/li>\n    <li><a href=\"http:\/\/blag.xkcd.com\/2007\/08\/20\/testing-the-9v-battery-hack-or-assault-on-battery\/\">9V batteries are just 6 AAAAs<\/a> in <a href=\"http:\/\/www.zbattery.com\/c.288557\/seriesparallel-pf.html\">series<\/a>. (That said, cut batteries open at your own risk!)<\/li>\n    <li>Your <a href=\"http:\/\/en.wikipedia.org\/wiki\/Car_battery#Terminal_voltage\">12V car battery<\/a> should actually be around 12.6V; a true 12V indicates that it&#8217;s largely drained. (Your car&#8217;s alternator should recharge the battery by providing ~13.8V when the car is running.)<\/li>\n    <li>There&#8217;s a lot of information out there about &#8220;memory effects&#8221; and such, and thus all sorts of confusing, contradictory information about recharging batteries. <a href=\"http:\/\/en.wikipedia.org\/wiki\/NiCad\">NiCd<\/a> (Nickel-Cadmium) batteries suffered from a strong <a href=\"http:\/\/en.wikipedia.org\/wiki\/Memory_effect\">memory effect<\/a>: if you routinely recharged them before they were completely drained, you would drastically decrease the charge the battery could hold. <a href=\"http:\/\/en.wikipedia.org\/wiki\/NiMH\">NiMH<\/a> (Nickel metal hydride) batteries reduced this effect, and <a href=\"http:\/\/en.wikipedia.org\/wiki\/LiIon\">LiIon<\/a>s (Lithium Ion) eliminate it. Thus &#8220;topping off&#8221; most newer batteries isn&#8217;t in and of itself a bad thing. However&#8230;<\/li>\n    <li>Batteries still have a limited &#8220;charge cycle,&#8221; the number of times you can recharge them. Thus recharging your battery any time it dips below 95% charge is going to wear it out prematurely. Where this really matters is laptop batteries: you charge your battery fully, unplug and shut down to bring your laptop to a meeting, and then plug in there. This is murder on the battery. <em>Some<\/em> laptop battery systems are &#8220;smart&#8221; about this and will simply not bother charging a basically-full battery, but as a general rule, if you&#8217;re <em>discharging<\/em> a battery, don&#8217;t recharge it until it starts to get low&#8230;<\/li>\n<\/ul>\n<p>Edit: An <a href=\"http:\/\/en.wikipedia.org\/wiki\/Alkaline_battery\">alkaline battery<\/a>, being, well, <a href=\"http:\/\/en.wikipedia.org\/wiki\/Alkali\">alkaline<\/a>, won&#8217;t actually leak acid, but <a href=\"http:\/\/en.wikipedia.org\/wiki\/Potassium_hydroxide\">potassium hydroxide<\/a>.<\/p>","protected":false},"excerpt":{"rendered":"<p>A few things I&#8217;ve learned about batteries lately: Rechargeable AA&#8217;s are 1.2V, whereas normal alkaline AA&#8217;s are 1.5V. I didn&#8217;t believe this at first, but it&#8217;s usually printed right on the battery (in unreasonably small print). Where this generally matters &hellip; <a href=\"https:\/\/blogs.n1zyy.com\/n1zyy\/2008\/07\/30\/unreasonably-much-information-about-batteries\/\">Continue reading <span class=\"meta-nav\">&rarr;<\/span><\/a><\/p>","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-947","post","type-post","status-publish","format-standard","hentry","category-uncategorized"],"_links":{"self":[{"href":"https:\/\/blogs.n1zyy.com\/n1zyy\/wp-json\/wp\/v2\/posts\/947","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blogs.n1zyy.com\/n1zyy\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blogs.n1zyy.com\/n1zyy\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blogs.n1zyy.com\/n1zyy\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/blogs.n1zyy.com\/n1zyy\/wp-json\/wp\/v2\/comments?post=947"}],"version-history":[{"count":0,"href":"https:\/\/blogs.n1zyy.com\/n1zyy\/wp-json\/wp\/v2\/posts\/947\/revisions"}],"wp:attachment":[{"href":"https:\/\/blogs.n1zyy.com\/n1zyy\/wp-json\/wp\/v2\/media?parent=947"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blogs.n1zyy.com\/n1zyy\/wp-json\/wp\/v2\/categories?post=947"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blogs.n1zyy.com\/n1zyy\/wp-json\/wp\/v2\/tags?post=947"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}