# Why does Lithium-ion batteries hate being plug in for a long time? **URL:** \ **Category:** Factual Questions\ **Created:** [May 27, 2024, 6:11pm UTC](https://boards.straightdope.com/t/why-does-lithium-ion-batteries-hate-being-plug-in-for-a-long-time/1002150 "2024-05-27T18:11:07Z")\ **Posts on this page:** 4\ **Page:** 2
**Author:** ![kanicbird](https://avatars.discourse-cdn.com/v4/letter/k/5f8ce5/32.png) [@kanicbird](https://boards.straightdope.com/u/kanicbird)\ **Post date:** [June 3, 2024, 1:05am UTC](https://boards.straightdope.com/t/why-does-lithium-ion-batteries-hate-being-plug-in-for-a-long-time/1002150/21 "2024-06-03T01:05:38Z")
Since you claim they throttle it to help reduce heat, I would say that it would unquestionably benefit from active cooling. The reason that they don’t is that a cell phone is not expected to last as long as a EV battery. Some may even say that is part of its planned obsolescence. But either way there is a different design criteria where you don’t need 10 yrs + battery life in a cell phone so you can afford more battery abuse. ---
**Author:** ![md-2000](https://avatars.discourse-cdn.com/v4/letter/m/9d8465/32.png) [@md-2000](https://boards.straightdope.com/u/md-2000)\ **Post date:** [June 3, 2024, 8:31pm UTC](https://boards.straightdope.com/t/why-does-lithium-ion-batteries-hate-being-plug-in-for-a-long-time/1002150/22 "2024-06-03T20:31:43Z")
> [@kanicbird](#): > > This was once thought to be the case but now in question. It does seem it’s not the fast charge so much but more the heat that fast charging causes. With proper thermal management it appears that fast charging does not significantly reduce battery life. But even with thermal management there still is a small hit on life, but just much smaller then without. OTOH, there was an article a few years ago about a Tesla that had 400,000 miles on it. It was a Model S used for taxi services between La and Las Vegas. At 180,000 miles it needed a new battery pack because a battery failed in the pack. The batteries were eplaced under warranty. At 220,000 more miles, it was still going strong. At my current rate, it will take me almost 20 years to reach that (mostly home charging). Not bad, considering the regular round trips meant fast charging multiple times a day and driving through the desert in fairly ot conditions. So “deteriorate” may not be as bad as it sounds. Teslas have good heat management. There are videos of them being driven on the Autobahn at 150mph. After about 40 minutes, the car slows to 55mph because the battery is getting too hot. Once the cooling has worked, it speed back up. Teslas use a massive array of cylindrical batteries (like bigger AA cells). Supposedly, the metal cases on each battery help. The one that had real problems was apparently the original Nissan Leaf, where they used soft-cell batteries. Te batteries would swell up and fail, many of these cars had lost half their very limited range within 2 or 3 years. (I have a MacBook Air, the bag battery swelled up once, the keyboard was visibly bent - eitherfrom being plugged in for weeks, or beingallowed to sit at zero for months. It was well out of warranty, but I ordered a new battery from Amazon and it’s been working fine ever since.) ---
**Author:** ![Francis\_Vaughan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/francis_vaughan/32/3093_2.png) [@Francis\_Vaughan](https://boards.straightdope.com/u/Francis_Vaughan)\ **Post date:** [June 4, 2024, 10:02am UTC](https://boards.straightdope.com/t/why-does-lithium-ion-batteries-hate-being-plug-in-for-a-long-time/1002150/23 "2024-06-04T10:02:49Z")
My car has a fan in the magnetic charger cubby designed to cool the phone. So it isn’t unknown. The Apple MagSafe system for phones could provide a heat sink if done right. Seems I’m a bit late with the idea. Razer do one. And there are other similar ideas. The use case however is hilarious. It provides power and cooling for people engaged in serious gaming on their phone. I guess that is legit. But I hope very niche. In my car I find that if the phone is doing the whole CarPlay thing it does chew a bit of power and get noticeably warm. So that plus charging might get to the point cooling is of value is unbelievable. ---
**Author:** ![md-2000](https://avatars.discourse-cdn.com/v4/letter/m/9d8465/32.png) [@md-2000](https://boards.straightdope.com/u/md-2000)\ **Post date:** [June 6, 2024, 4:53pm UTC](https://boards.straightdope.com/t/why-does-lithium-ion-batteries-hate-being-plug-in-for-a-long-time/1002150/24 "2024-06-06T16:53:57Z")
Here’s another one… > **[Tesla Model S still running with original battery and motors at 430k miles](https://www.teslarati.com/tesla-model-s-original-battery-motors-430k-miles/)** > > The Tesla Model S 90D has managed to keep its original battery pack and electric motors — even after a whopping 430k miles on the odometer. how many gas automobiles can go that long without a major engine rebuild and a lot of replacement parts? [Previous page](https://boards.straightdope.com/t/why-does-lithium-ion-batteries-hate-being-plug-in-for-a-long-time/1002150.md?page=1)