<story><title>Ask HN: Should I unplug my laptop charger at 100%?</title><text>I have talked to numerous people and there is no set consensus on whether I should be unplugging my laptop charger when it is fully charged.</text></story><parent_chain><item><author>gpvos</author><text>So what my laptop should do &lt;i&gt;automatically&lt;/i&gt; is to stop charging once it hits ~90%, and start charging again when it hits ~40%. And the OS should give me an easy-to-reach option to &amp;quot;charge to 100%&amp;quot; for when I&amp;#x27;m about to make a trip. Why hasn&amp;#x27;t anyone implemented this yet?</text></item><item><author>bkanber</author><text>Source: I have a master&amp;#x27;s degree in mechanical engineering in hybrid vehicle powertrains, and a big part of my research was battery technology. I spent some time working with the folks at National Semiconductor learning this, so I have several primary sources.&lt;p&gt;Disclaimer: my knowledge of the field is from ca 2010.&lt;p&gt;1) Lots of deep discharge cycles do negatively affect battery life. Try not to jump between 0% and 100% too much.&lt;p&gt;2) Li-ion batteries do not love being at 100% SOC (state of charge). As batteries become more dense, the membranes become thinner. High SOC equates to high chemical potential, which will break down membranes faster. As such, avoid leaving your battery at 100%. This wasn&amp;#x27;t as much of a problem with older batteries with thicker membranes, but is becoming more and more an issue as we try to squeeze every ounce of density out of batteries.&lt;p&gt;3) Roughly 70% SOC is where a battery is happiest, but the whole range of ~30-80% is pretty happy for a li ion cell. Try to keep your battery at ~70% or so overnight, at 50% or so for long sleeps.&lt;p&gt;A good usage pattern: plug in and let charge to 90%, unplug and use for a couple of hours, plug back in at 50% or so, rinse and repeat.</text></item></parent_chain><comment><author>jen729w</author><text>See Siracusa&amp;#x27;s analysis of this suggestion.&lt;p&gt;&lt;a href=&quot;http:&amp;#x2F;&amp;#x2F;atp.fm&amp;#x2F;episodes&amp;#x2F;33-a-30-minute-skip-button&quot; rel=&quot;nofollow&quot;&gt;http:&amp;#x2F;&amp;#x2F;atp.fm&amp;#x2F;episodes&amp;#x2F;33-a-30-minute-skip-button&lt;/a&gt;&lt;p&gt;TL;DR: good idea, but people will forget and become shitty when their laptop isn&amp;#x27;t at 100% when they go on a trip.</text></comment>
<story><title>Ask HN: Should I unplug my laptop charger at 100%?</title><text>I have talked to numerous people and there is no set consensus on whether I should be unplugging my laptop charger when it is fully charged.</text></story><parent_chain><item><author>gpvos</author><text>So what my laptop should do &lt;i&gt;automatically&lt;/i&gt; is to stop charging once it hits ~90%, and start charging again when it hits ~40%. And the OS should give me an easy-to-reach option to &amp;quot;charge to 100%&amp;quot; for when I&amp;#x27;m about to make a trip. Why hasn&amp;#x27;t anyone implemented this yet?</text></item><item><author>bkanber</author><text>Source: I have a master&amp;#x27;s degree in mechanical engineering in hybrid vehicle powertrains, and a big part of my research was battery technology. I spent some time working with the folks at National Semiconductor learning this, so I have several primary sources.&lt;p&gt;Disclaimer: my knowledge of the field is from ca 2010.&lt;p&gt;1) Lots of deep discharge cycles do negatively affect battery life. Try not to jump between 0% and 100% too much.&lt;p&gt;2) Li-ion batteries do not love being at 100% SOC (state of charge). As batteries become more dense, the membranes become thinner. High SOC equates to high chemical potential, which will break down membranes faster. As such, avoid leaving your battery at 100%. This wasn&amp;#x27;t as much of a problem with older batteries with thicker membranes, but is becoming more and more an issue as we try to squeeze every ounce of density out of batteries.&lt;p&gt;3) Roughly 70% SOC is where a battery is happiest, but the whole range of ~30-80% is pretty happy for a li ion cell. Try to keep your battery at ~70% or so overnight, at 50% or so for long sleeps.&lt;p&gt;A good usage pattern: plug in and let charge to 90%, unplug and use for a couple of hours, plug back in at 50% or so, rinse and repeat.</text></item></parent_chain><comment><author>tertius</author><text>I have this as &amp;quot;conservation mode&amp;quot; on my Lenovo Yoga Pro 2, and probably all new Lenovos.</text></comment>