# Power banks for modern ultra low power laptops/tablets **URL:** \ **Category:** Openbaar\ **Created:** [September 26, 2026, 10:59pm UTC](https://forum.revspace.nl/t/power-banks-for-modern-ultra-low-power-laptops-tablets/1115 "2026-09-26T22:59:26Z")\ **Posts on this page:** 5\ **Page:** 1
**Author:** ![jaclu](https://forum.revspace.nl/letter_avatar_proxy/v4/letter/j/6f9a4e/32.png) [@jaclu](https://forum.revspace.nl/u/jaclu)\ **Post date:** [September 26, 2026, 10:59pm UTC](https://forum.revspace.nl/t/power-banks-for-modern-ultra-low-power-laptops-tablets/1115/1 "2026-09-26T22:59:27Z")
I have tried several of the higher power Anker power banks, but for a device only needing 5-10W on average they mostly suck… Not that they don’t work, they do. However they seem to have BMS that in it self is a noticeable drain when only supplying 4-5W, like keeping a m-series MacBook air or iPad at their target 80% charge as you use it. They end up essentially self draining, and delivering only half of the stated power, sometimes even less. I have found that more limited 20W 20Ah power banks actually delivers more than double the more actual Wh per charge than at least the 25Ah-27Ah laptop rated power banks I have tried so far. The major drawback with 20-40W power banks is they take forever to charge. Often like 4-5h, vs the 200W+ power banks that charges in an hour or so. Is it impossible to create a high power BMS without noticeable self drain, or is this just a usage scenario that Anker has not bothered to take into account? Does anybody here know of any power banks that can charge at 100W+, without self draining hugely on low output scenarios? Sure some might say, dont trickle charge with them, drain your device and then quickly recharge it at a rate more suitable for “laptop” power banks, but that perspective misses a core point, power banks are cheap, and laptops are not, so why not have the power bank age out due to cycles instead of the more expensive device? ---
**Author:** ![FooBar](https://forum.revspace.nl/user_avatar/forum.revspace.nl/foobar/32/19_2.png) [@FooBar](https://forum.revspace.nl/u/FooBar)\ **Post date:** [September 26, 2026, 11:36pm UTC](https://forum.revspace.nl/t/power-banks-for-modern-ultra-low-power-laptops-tablets/1115/2 "2026-09-26T23:36:51Z")
Bigger power-output capacity means bigger/more powerful components, with a higher self-discharge… Check the powerbank best-buy-guides… they have more info than anyone here can give you > **[DPG Media Privacy Gate](https://myprivacy.dpgmedia.nl/consent?siteKey=kzz6o4y8ybwvpkea&callbackUrl=https%3A%2F%2Ftweakers.net%2Fprivacygate-confirm%3FredirectUri%3D%252Fzoeken%252F%253Fkeyword%253Dpowerbank%252Bbbg&isLoggedIn=false)** ---
**Author:** ![jaclu](https://forum.revspace.nl/letter_avatar_proxy/v4/letter/j/6f9a4e/32.png) [@jaclu](https://forum.revspace.nl/u/jaclu)\ **Post date:** [September 27, 2026, 7:08am UTC](https://forum.revspace.nl/t/power-banks-for-modern-ultra-low-power-laptops-tablets/1115/3 "2026-09-27T07:08:50Z")
tweakers generally has good power bank coverage, but just as all the other sources I have checked, they fail to mention anything about how a power bank performs in low drain situations. I might be missing something, but shouldn’t just putting the power bank at a static low power drain like 1 or 2 W and observe Wh delivered, then comparing that to what is delivered at higher more typical drains give a good idea of the BMS self-drain, or would that over simplify things, and miss something crucial? ---
**Author:** ![FooBar](https://forum.revspace.nl/user_avatar/forum.revspace.nl/foobar/32/19_2.png) [@FooBar](https://forum.revspace.nl/u/FooBar)\ **Post date:** [September 27, 2026, 11:23am UTC](https://forum.revspace.nl/t/power-banks-for-modern-ultra-low-power-laptops-tablets/1115/4 "2026-09-27T11:23:55Z")
They have stats for a 2A discharge (which is still 10W) … anything lower than that, you should probably not use a powerbank for (disconnect and use internal battery, or plug in a wall outlet). ---
**Author:** ![jaclu](https://forum.revspace.nl/letter_avatar_proxy/v4/letter/j/6f9a4e/32.png) [@jaclu](https://forum.revspace.nl/u/jaclu)\ **Post date:** [September 27, 2026, 3:47pm UTC](https://forum.revspace.nl/t/power-banks-for-modern-ultra-low-power-laptops-tablets/1115/5 "2026-09-27T15:47:53Z")
at 15V my drain is closer to 0.5A so the 2A numbers don’t mean much unfortunately. And sure, with current power banks low power charging at 4-5W is highly inefficient, but still much chesper than having to replace the batteries in a laptop or tablet