this post was submitted on 01 Feb 2024
33 points (90.2% liked)

No Stupid Questions

35004 readers
724 users here now

No such thing. Ask away!

!nostupidquestions is a community dedicated to being helpful and answering each others' questions on various topics.

The rules for posting and commenting, besides the rules defined here for lemmy.world, are as follows:

Rules (interactive)


Rule 1- All posts must be legitimate questions. All post titles must include a question.

All posts must be legitimate questions, and all post titles must include a question. Questions that are joke or trolling questions, memes, song lyrics as title, etc. are not allowed here. See Rule 6 for all exceptions.



Rule 2- Your question subject cannot be illegal or NSFW material.

Your question subject cannot be illegal or NSFW material. You will be warned first, banned second.



Rule 3- Do not seek mental, medical and professional help here.

Do not seek mental, medical and professional help here. Breaking this rule will not get you or your post removed, but it will put you at risk, and possibly in danger.



Rule 4- No self promotion or upvote-farming of any kind.

That's it.



Rule 5- No baiting or sealioning or promoting an agenda.

Questions which, instead of being of an innocuous nature, are specifically intended (based on reports and in the opinion of our crack moderation team) to bait users into ideological wars on charged political topics will be removed and the authors warned - or banned - depending on severity.



Rule 6- Regarding META posts and joke questions.

Provided it is about the community itself, you may post non-question posts using the [META] tag on your post title.

On fridays, you are allowed to post meme and troll questions, on the condition that it's in text format only, and conforms with our other rules. These posts MUST include the [NSQ Friday] tag in their title.

If you post a serious question on friday and are looking only for legitimate answers, then please include the [Serious] tag on your post. Irrelevant replies will then be removed by moderators.



Rule 7- You can't intentionally annoy, mock, or harass other members.

If you intentionally annoy, mock, harass, or discriminate against any individual member, you will be removed.

Likewise, if you are a member, sympathiser or a resemblant of a movement that is known to largely hate, mock, discriminate against, and/or want to take lives of a group of people, and you were provably vocal about your hate, then you will be banned on sight.



Rule 8- All comments should try to stay relevant to their parent content.



Rule 9- Reposts from other platforms are not allowed.

Let everyone have their own content.



Rule 10- Majority of bots aren't allowed to participate here.



Credits

Our breathtaking icon was bestowed upon us by @Cevilia!

The greatest banner of all time: by @TheOneWithTheHair!

founded 1 year ago
MODERATORS
top 23 comments
sorted by: hot top controversial new old
[–] [email protected] 23 points 6 months ago (1 children)

Be careful buying powerbanks with high capacity and wattage. Get a trusted brand and not a cheap one from China. My sister left one of these charging for an hour while she went to a friend's house and came back to a raging fire in her apartment.

[–] [email protected] 8 points 6 months ago* (last edited 6 months ago) (1 children)

Just don't buy any extremely cheap powerbanks unless you know how to inspect and test them.

The issue is not only about the number of cells, but it's also about the construction of the charger. Obviously, more poorly managed cells can create more of a problem, but most lithium batteries die violently when damaged, regardless of size. (Lithium batteries are so common now, it's easy to forget that they can be dangerous. Their construction is generally better these days, but that alone doesn't mitigate all risk.)

Unfortunately, powerbanks are usually sealed so they are hard to open and inspect. If you do get them open, you need to understand what you are looking for, which can be challenging. There is also a risk of damaging a cell when you open them, which is also bad.

Name brand chargers simply give you someone to sue. (Random knock-off brands don't.) Because of the liability, name brands usually have better construction and go through some kind of safety testing. Edit: The batteries don't need to be "name brand". If you bought a random powerbank at a reputable store, the store itself may assume the liability. (Large stores can distribute name brand products under a house name, in some cases.)

Wiring problems, mismatched cells without protection and poorly designed charging circuits are usually the issues.

Bonus! bigclive doing some destructive testing on batteries: https://youtu.be/EgtKwxzgggg

[–] [email protected] 2 points 6 months ago

Lithium batteries can catastrophically fail for a number of reasons. Internal shorts from discharging too low, external shorts, over charging, over discharging, physical damage, and heat to name a few.

If your charging circuit isn't balance charging the cells properly or the overcharge protection fails, then it can cause many of those issues to happen much faster.

Moral of the story: never leave a charging battery unattended.

[–] [email protected] 11 points 6 months ago (1 children)

5000 mAh is pretty small. Is that a typo?

[–] [email protected] 4 points 6 months ago (1 children)

Nope. I need a small power bank that will get me around 50% as fast as possible on the go. I have a 10 000 ( 30w) but it's too big and heavy.

[–] [email protected] 3 points 6 months ago* (last edited 6 months ago) (2 children)

You need to look at other brands then. I also have a 10k one from anker that is slim and fits in a pocket easy peasy. If you have an iPhone or are willing to buy a new case there are also ones that use magsafe to stick to the back of your phone and charge it wirelessly.

https://a.co/d/hYaim74

You could also look and see if anyone has made a battery case for your phone. This way you aren't carrying two things.

[–] [email protected] 3 points 6 months ago

That's the one I have. It's fantastic.

[–] [email protected] 2 points 6 months ago* (last edited 6 months ago) (2 children)

Thanks for the link, I already have a slim 10k power bank. I still think it's too bulky for my use.

[–] [email protected] 4 points 6 months ago

Cut it in half, it’ll be smaller.

[–] [email protected] 2 points 6 months ago

They have others in the 5k range that are half the size. And ankers recent banks definitely charge if not as fast, close enough to wall speed.

[–] [email protected] 6 points 6 months ago (1 children)

Just thought about this, isn't it a bit silly that we all use milli Ah while all the values are above the thousands? Like, 5000 mAh is just 5 Ah

[–] ironhydroxide 20 points 6 months ago* (last edited 6 months ago) (2 children)

It's because you can get more when measuring in mA than you can in A.

5000 mAh means you can get 5000 hours out when pulling at 1mA. 5 Ah means you can get 5 hours when pulling at 1A.

You'd think these are commutative, but battery chemistry doesn't work that way. The harder you load, the less actual power you can get. So a battery that can provide 1mA for 5000 hours can't necessarily provide 1A for 5 hours.

[–] [email protected] 6 points 6 months ago (1 children)

Damn, interesting! And that chemist sounding name sure does add extra credibility

[–] ironhydroxide 9 points 6 months ago

Don't read too much into that.

My chemistry is rust(y).

[–] [email protected] 3 points 6 months ago (1 children)

And not to mention the discharge efficiency curve. For LiPo batteries you will see a sort of “coasting” when the battery is at about 3.7v if your load is sufficiently small. But when it’s at 4.0v it will seem to drain quicker.

I have a 10000mAh battery powering a device that uses 10uA every 30 minutes for about 10 seconds. On one charge it should last about 1 year maybe a little more. The first 2 months it seemed like it lost a lot more juice than was expected but since then it settled in and is now ahead of its estimate. Which means it will speed back up as it goes down below 3.7v.

[–] [email protected] 1 points 6 months ago

This is why the nominal voltage of lithium batteries is 3.7v, even though you charge them to 4.2v.

[–] [email protected] 3 points 6 months ago* (last edited 6 months ago) (2 children)

I bought this one a couple of years ago. I ended up not using it as planned because it wouldn't power my laptop. It claims to output 130w. I'm considering using it to power a heated bird bath and possibly an outside cam if I can figure out a less expensive way to keep it out of the elements.

https://a.co/d/1pq7CPg

[–] [email protected] 1 points 6 months ago

You can get water proof electric junction boxes at your local big box hardware store for a few bucks. Get one with only one port and use a cable gland to seal the cable. You can also get waterproof connector pigtails so you can remove the battery without messing with the case.

[–] [email protected] 1 points 6 months ago (1 children)

Thanks, but that one will be hard to fit in my pocket 🙂 I was looking for 5 000 mAh.

[–] [email protected] 4 points 6 months ago

if you're just looking for it to fit in your pocket, i have a zendure brand one that is barely bigger than a credit card in its dimensions, but its 10k mah, 45W. It's about an inch tall. I know it's not 5,000 like you are asking, but might fit the bill size wise

[–] [email protected] 1 points 6 months ago
[–] [email protected] 1 points 6 months ago* (last edited 6 months ago) (1 children)

Quickest 5k Ive personally seen is the Anker Hybrid at 20W

[–] [email protected] 1 points 6 months ago

For information, I bought the Anker Nano Power Bank 5 000 (22.5W, Built-In USB-C Connector). Not 30 W or slim as I was aiming for, but with this one I don't need to think about a cable. Only weights 100 g, half of the weight of my slim 30w 10k power bank.