/technologies/power-management/b/blog/posts/energy-left-in-dead-batteriesHi Element14 Community! Traditional alkaline batteries tend to &quot;die&quot; at the most inconvenient times. I used to I have them in devices like wireless mouse and keyboards, and it felt that the batteries were draining fairly quickly, catc...en-USTelligent Community 12https://community.element14.com/technologies/power-management/b/blog/posts/energy-left-in-dead-batteriesTue, 03 Feb 2026 20:01:30 GMT93d5dcb4-84c2-446f-b2cb-99731719e767:92d669eb-7ea7-4578-bd56-dc3d5e4bfb9bDAB0<p>Very good post.</p> <p>It is amazing how much power is wasted in batteries after they fall below the usable voltage level.</p><img src="https://community.element14.com/aggbug?PostID=29498&AppID=4&AppType=Weblog&ContentType=0" width="1" height="1">https://community.element14.com/technologies/power-management/b/blog/posts/energy-left-in-dead-batteriesMon, 02 Feb 2026 16:21:57 GMT93d5dcb4-84c2-446f-b2cb-99731719e767:92d669eb-7ea7-4578-bd56-dc3d5e4bfb9bbeacon_dave0<p>Nice post.</p> <p>It would be interesting to do a load test with one of the Li-ion rechargeable AA batteries that has&nbsp;a built-in buck convertor. In theory they are supposed to give a stable output for around 95% of their capacity.</p> <p>I have been known to take two dead AA batteries in series at a time and connect it to a <a href="https://www.dfrobot.com/product-1475.html" rel="noopener noreferrer nofollow" target="_blank" data-e14adj="t">joule thief boost convertor</a> to output 5V which then re-charges a USB power bank. One battery will fail first so just swap it with the next one and keep going.</p> <p><span>Apocalypse ready&nbsp;[emoticon:599cc6d89e2145289084ee73d7cb364b]</span></p><img src="https://community.element14.com/aggbug?PostID=29498&AppID=4&AppType=Weblog&ContentType=0" width="1" height="1">https://community.element14.com/technologies/power-management/b/blog/posts/energy-left-in-dead-batteriesMon, 02 Feb 2026 16:06:42 GMT93d5dcb4-84c2-446f-b2cb-99731719e767:92d669eb-7ea7-4578-bd56-dc3d5e4bfb9bbeacon_dave0<blockquote> <p><em>&quot;...Otherwise, looks like there is not much use to these dead batteries...&quot;</em></p> </blockquote> <p><a href="/challenges-projects/element14-presents/project-videos/w/documents/27807/using-dead-batteries-to-test-for-dead-batteries----episode-571" data-e14adj="t">Using Dead Batteries to Test for Dead Batteries</a>&nbsp;[emoticon:c4563cd7d5574777a71c318021cbbcc8]</p><img src="https://community.element14.com/aggbug?PostID=29498&AppID=4&AppType=Weblog&ContentType=0" width="1" height="1">https://community.element14.com/technologies/power-management/b/blog/posts/energy-left-in-dead-batteriesMon, 02 Feb 2026 14:51:50 GMT93d5dcb4-84c2-446f-b2cb-99731719e767:92d669eb-7ea7-4578-bd56-dc3d5e4bfb9bbattlecoder0<p>&nbsp;This was a very interesting post to read. I regularly &quot;save&quot; batteries that were in power-hungry devices (that no longer have enough juice to power them)&nbsp; to use them in those that don&#39;t drain that much current, hoping to squeeze as much energy as I can from them. Not to save money but rather to spare the environment from more e-waste.</p> <p>Love how you actually took the time to measure how much energy was still there in your batteries. Very nice work!</p><img src="https://community.element14.com/aggbug?PostID=29498&AppID=4&AppType=Weblog&ContentType=0" width="1" height="1">https://community.element14.com/technologies/power-management/b/blog/posts/energy-left-in-dead-batteriesMon, 02 Feb 2026 13:55:06 GMT93d5dcb4-84c2-446f-b2cb-99731719e767:92d669eb-7ea7-4578-bd56-dc3d5e4bfb9bdougw0<p>Great work - I always wondered the same thing...</p><img src="https://community.element14.com/aggbug?PostID=29498&AppID=4&AppType=Weblog&ContentType=0" width="1" height="1">https://community.element14.com/technologies/power-management/b/blog/posts/energy-left-in-dead-batteriesSun, 01 Feb 2026 17:11:00 GMT93d5dcb4-84c2-446f-b2cb-99731719e767:92d669eb-7ea7-4578-bd56-dc3d5e4bfb9bkmikemoo0<p>[mention:3802a729b7164b2aaed003ebb80381cb:e9ed411860ed4f2ba0265705b8793d05]&nbsp;Nice experiment.&nbsp; I know that I wonder how much capacity I&#39;m throwing away when I change out batteries.&nbsp;[emoticon:fbd079a1c4f748c5a234faee215de9cc]</p><img src="https://community.element14.com/aggbug?PostID=29498&AppID=4&AppType=Weblog&ContentType=0" width="1" height="1">