Li-ion protective circuitry requires at least a little battery power to energize itself, so a Li-ion battery typically reserves the last 3-4% of the battery charge for internal use. That way, when a low-battery condition forces the device to shut down, the battery still has enough power left to keep the protective circuitry alive and ready to accept the next recharge.<\/p>\n\n\n\n
But if the battery is drained so far that the protective circuitry goes dead, the inert circuitry prevents normal recharging — a “fail safe” measure to ensure that the battery can’t be recharged without the protective circuitry alive.<\/p>\n\n\n\n
So: When a Li-ion battery won’t accept a charge, it’s no longer safe to use.<\/p>\n\n\n\n
![\"\"](\"https:\/\/i0.wp.com\/langa.com\/wp-content\/uploads\/2019\/10\/18650-batteries.jpg?resize=241%2C256&ssl=1\")
Can you get around it? Maybe, with the right tools and knowledge. But you\u2019re asking for trouble: Again, remember those hoverboard fires?<\/p>\n\n\n\n
Besides, why would you take the risk? Individual 18650-sized Li-ion batteries\/cells aren’t expensive: The ones in the photo above cost about $6 each, and last for hundreds and hundreds of recharges.<\/p>\n\n\n\n
Is it worth risking a fire to save $6?<\/p>\n\n\n\n
Permalink: https:\/\/langa.com\/?p=3551<\/a><\/strong><\/em><\/p>\n\n\n\n COMMENT \/ QUESTION<\/strong> on THIS ITEM?<\/strong> See the<\/em> Comment box<\/strong> at bottom of this page!<\/em> Not a good idea. The protective circuitry (in the Li-ion battery or in the device that the battery powers) is designed to prevent dangerous over- and undercharging, which can cause the battery to overheat and catch fire. (Remember all those hoverboard fires a couple years ago? That’s what you get when you abuse a Li-ion…<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"om_disable_all_campaigns":false,"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"jetpack_post_was_ever_published":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":true,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2}},"categories":[7,30,12],"tags":[],"class_list":["post-3551","post","type-post","status-publish","format-standard","hentry","category-a-reader-asks","category-hardware","category-smartphones"],"aioseo_notices":[],"jetpack_publicize_connections":[],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"jetpack_shortlink":"https:\/\/wp.me\/paaiox-Vh","jetpack-related-posts":[{"id":2505,"url":"https:\/\/langa.com\/index.php\/2019\/04\/08\/how-to-make-lithium-ion-batteries-last-for-years\/","url_meta":{"origin":3551,"position":0},"title":"How to make lithium-ion batteries last for years","author":"Fred Langa","date":"2019-04-08","format":false,"excerpt":"The older column reprinted below was originally published in the August 13, 2015 , Windows Secrets newsletter. This older content supplements brand-new content posted today (April 8, 2019) in the AskWoody Plus newsletter, available here. An upcoming column will update and refine the information below. (I\u2019m reprinting selected Windows Secrets\u2026","rel":"","context":"In "AskWoody Plus"","block_context":{"text":"AskWoody Plus","link":"https:\/\/langa.com\/index.php\/category\/askwoody-plus\/"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/langa.com\/wp-content\/uploads\/2019\/04\/W20150813-TS-BatteryFromTop.png?resize=350%2C200&ssl=1","width":350,"height":200},"classes":[]},{"id":5117,"url":"https:\/\/langa.com\/index.php\/2020\/06\/02\/why-does-a-device-with-no-battery-have-enough-battery-to-show-me-there-is-no-battery-yet-does-not-let-me-do-what-i-want-to\/","url_meta":{"origin":3551,"position":1},"title":"“Why does a device with no battery have enough battery to show me there is no battery, yet does not let me do what I want to?”","author":"Fred Langa","date":"2020-06-02","format":false,"excerpt":"(Questioner requested anonymity) On Li-ion consumer devices, \"0% battery\u201d doesn't mean \u201cno energy\u201d but rather \u201cno energy available for anything except to wait for the next recharge.\u201d That's because Li-ion batteries require careful regulation of volts, amps, and temperature. The charging circuits need to save the last few percent of\u2026","rel":"","context":"In "A reader asks..."","block_context":{"text":"A reader asks...","link":"https:\/\/langa.com\/index.php\/category\/a-reader-asks\/"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/langa.com\/wp-content\/uploads\/2020\/05\/low-battery-indicator-stylized-rf-e1590776520349.jpg?fit=350%2C290&ssl=1&resize=350%2C200","width":350,"height":200},"classes":[]},{"id":3656,"url":"https:\/\/langa.com\/index.php\/2019\/10\/29\/how-long-does-it-take-for-a-li-ion-battery-to-degrade\/","url_meta":{"origin":3551,"position":2},"title":"“How long does it take for a Li-ion battery to degrade?”","author":"Fred Langa","date":"2019-10-29","format":false,"excerpt":"(Answer requested by Jake Timchak) Degrade by how much? Lithium-ion batteries are \u201cconsumables\u201d that inevitably get used up, even just sitting on the shelf. Li-ion batteries actually start degrading (very slowly) the moment they\u2019re assembled at the factory. Each discharge\/recharge cycle then accelerates the irreversible chemical changes in the battery,\u2026","rel":"","context":"In "A reader asks..."","block_context":{"text":"A reader asks...","link":"https:\/\/langa.com\/index.php\/category\/a-reader-asks\/"},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]},{"id":2960,"url":"https:\/\/langa.com\/index.php\/2019\/06\/20\/what-is-the-fastest-and-safest-method-for-putting-out-a-lithium-ion-battery-fire\/","url_meta":{"origin":3551,"position":3},"title":"“What is the fastest and safest method for putting out a lithium-ion battery fire?”","author":"Fred Langa","date":"2019-06-20","format":false,"excerpt":"(Answer requested by Richard Janezic) LI-ion batteries are considered Class B (flammable liquids\/gases) fire hazards (info). LI-ion fires are ferocious, and the gases are nasty. If there's a fire, unplug the device (if plugged in), call the fire department, and then use an ABC- or BC-rated fire extinguisher (info) to\u2026","rel":"","context":"In "A reader asks..."","block_context":{"text":"A reader asks...","link":"https:\/\/langa.com\/index.php\/category\/a-reader-asks\/"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/img.youtube.com\/vi\/YuKF8XfCVKQ\/0.jpg?resize=350%2C200","width":350,"height":200},"classes":[]},{"id":5057,"url":"https:\/\/langa.com\/index.php\/2020\/05\/21\/what-will-happen-if-i-dont-replace-immediately-a-swollen-lithium-ion-battery\/","url_meta":{"origin":3551,"position":4},"title":"“What will happen if I don’t replace immediately a swollen lithium ion battery?”","author":"Fred Langa","date":"2020-05-21","format":false,"excerpt":"(Answer requested by Arnielyn Arellano) When a Li-ion battery bulges, it usually means a near-failure generated toxic, flammable gases. Your battery's case did its job --- it contained the gases so far --- but at very high internal pressure (hence the swelling). In other words, your battery\u2019s near-failure has turned\u2026","rel":"","context":"In "A reader asks..."","block_context":{"text":"A reader asks...","link":"https:\/\/langa.com\/index.php\/category\/a-reader-asks\/"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/img.youtube.com\/vi\/0nrsoMsEMNU\/0.jpg?resize=350%2C200","width":350,"height":200},"classes":[]},{"id":3618,"url":"https:\/\/langa.com\/index.php\/2019\/10\/16\/how-do-you-fix-a-charge-after-your-phone-has-not-charged-for-a-month\/","url_meta":{"origin":3551,"position":5},"title":"“How do you fix a charge after your phone has not charged for a month?”","author":"Fred Langa","date":"2019-10-16","format":false,"excerpt":"Um, plug it in? If the phone (or any lithium-ion device) was put away healthy, turned off, and with a reasonable charge (manufacturers use 30\u201340% for storage), the battery should be fine for months. If the battery was allowed to run all the way down, and the phone was stored\u2026","rel":"","context":"In "A reader asks..."","block_context":{"text":"A reader asks...","link":"https:\/\/langa.com\/index.php\/category\/a-reader-asks\/"},"img":{"alt_text":"","src":"","width":0,"height":0},"classes":[]}],"jetpack_likes_enabled":false,"_links":{"self":[{"href":"https:\/\/langa.com\/index.php\/wp-json\/wp\/v2\/posts\/3551","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/langa.com\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/langa.com\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/langa.com\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/langa.com\/index.php\/wp-json\/wp\/v2\/comments?post=3551"}],"version-history":[{"count":5,"href":"https:\/\/langa.com\/index.php\/wp-json\/wp\/v2\/posts\/3551\/revisions"}],"predecessor-version":[{"id":3575,"href":"https:\/\/langa.com\/index.php\/wp-json\/wp\/v2\/posts\/3551\/revisions\/3575"}],"wp:attachment":[{"href":"https:\/\/langa.com\/index.php\/wp-json\/wp\/v2\/media?parent=3551"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/langa.com\/index.php\/wp-json\/wp\/v2\/categories?post=3551"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/langa.com\/index.php\/wp-json\/wp\/v2\/tags?post=3551"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}![\"[seperator]\"](\"https:\/\/i0.wp.com\/langa.com\/wp-content\/uploads\/2019\/02\/SEPERATOR-short-grey.png?resize=104%2C6\")
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