Most of my electronics don't need a fast charger, and fast charging tends to reduces battery lifespan. So I'm looking for a slow charger (preferably 2 or 3 output) with max 500mA output per port. Any pointers where best to look for one (that won't burn down the house or electrocute me)?
Where to buy slow (i.e. 500mA) USB charger?
askvictor on 03/08/2024 - 13:19
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I said won't burn down the house or electrocute me
OP can go to any phone supplier to buy a standard 5V charger.
The AMPs dont matter OP as your devices will only draw as much current as they require.So on that point you can keep using your current charger!
So I'm looking for a slow charger (preferably 2 or 3 output) with max 500mA output per port
You…
OP can go to any phone supplier to buy a standard 5V charger.
The AMPs dont matter OP as your devices will only draw as much current as they require.
So on that point you can keep using your current charger!The amps do matter here, he wants them limited to .5A to slow charge!!! Do you even read?
The amps do matter here, he wants them limited to .5A to slow charge!!! Do you even read?
I don't think that's a good idea.
so if you are saying OP's device actually charges at like 5V/2A, but they want to limit the charge with a 5V/500mA charger. that means the 5V/500mA charger is running at maximum for basically the entire charge.
in my experience I actually tried this because I also used to think slow charge was better for battery, one time I touched the charger and it was VERY hot. it was an apple 5V/1A charger so should have been safe but the charger was still so hot to touch I couldn't hold it. if you left something like this overnight there is a real risk of something melting in the charger.
for example if you have a device charges at 5V/2A, and you use a 5V 2A charger the amount of time it's actually drawing 2A is limited. because it's able to wind up and wind down properly.
if you max out and use a 5V 1A charger is basically almost constantly charges at 1A because it's trying to draw more and doesn't have the room to wind up and down. if you do it with a 5V 500mA charger it will be even worse. this is my experience with all types of charges. I tried to charge my 12Ah power pack with a Eufy 12V 2A charger, when the power pack supports up to 12V/18V/24V 2A. the Eufy charger got extremely hot and stayed that way during the whole charge. after seeing how hot it got I decided not to use that charger anymore, even if it was only going to be charging for 4 hours.
you might think it's in extreme cases only but no I also experienced it with something common like a phone. my phone came with 20W charger but I once charged it with a 5W charger and the 5W charger became very very hot.
@n3ck3ntry8bort0rgasm: also forgot to mention when the heat is this intense, it travels to the USB connector down the wire to the device (yes the wire actually gets warm) and so your phone etc gets even warmer.
Buy a usb 2.0 hub
just be careful that it actually does power and isn't just data.
Many hubs just connect the power lines directly, so won't limit current.
I could be wrong, but don't devices just draw the amount of current it can handle (or needs) regardless of the charger's output?
USB has a system where the charger tells the device how much it can supply. Early USB versions do this with resistance across the data lines, and the device will change its charging rate accordingly. USB-C has a more complicated negotiation scheme.
USB ports in devices are often limited to 500mA. Try your computer/TV/stereo etc.
1-2A isn't going to cause issues with battery life, not compared to the 20-30A that usually indicates "fast charging" these days.
They key issue is heat, and batteries are designed to handle a lot more of it than they used to.
USB PD maxes out at 5A. With newer standards will do up to 48V.
Op Shops?
I've also noticed many of the generic chargers like ones from Kmart with the 2x USB-A are obviously going to be max 1A per port, typically less. I'd personally still trust those more than ones like Heymix.
Most of my electronics don't need a fast charger, and fast charging tends to reduces battery lifespan
I don't think this is a thing to worry about. Things that are smart and expensive enough to have fast charging capabilities (i.e. phones and laptops) will also have the intelligence to fast chart up to a partial full percentage, and then slow down for the final part of the charge.
I believe that it's fast charging all the way to full (and possibly the associated heat of this) which tends to stress the battery.
I went through this last year when I was looking for a charger that did even less, like 100ma or 200ma, for when you're charging old cheap gadgets, or for when using a phone with usb tethering and you don't want the battery at 100% constantly.
Care to share what you found as well?
Well, I learned that while there are many chargers from before 2010 that are only rated to deliver 500ma, generally the power limiting is done client side, so what will happen is the voltage drops down to 4v and then your phone or whatever will slow the charge rate, but keep flicking up and down as it tries to negotiate a higher rate. Not really a clean solution. It would be better in that case to control it from your phone, but you'd probably need it to be jailbroken.
Easiest, practical solution I found was just to attach a resistor inline with the charging cable. 5v at 500ma is 10 ohms, so if you put a 5ohm resistor inline it's going to drop quite a bit of voltage. You could possibly get away with just 1 or 2 ohms. Maybe a 10ohm potentiometer.
Best solution is probably to get a buck converter with a current limiter, connect it to a 12v power pack and then set it to 5v500ma
The USB specs for USB 2.0 A ports is limited to 500mA. Any charger which is outputting more on a USB A port is using some proprietary protocol like Qualcomm Quick Charge where you need to have both the charger and the cable supporting the protocol.
So if you get some simple USB 2.0 cables with USB A port on one side it should be limited to 500mA if the charger follow the USB specs.
Maybe some chargers will output a bit more but I don't think they would do more than 1A.There's also USB BC.
not sure what you mean.
I have an old 5V/1A USB-A charger and a USB power meter that shows how much is being drawn. if I plug something like my smart watch to charge, the meter shows 5V/50mA. that's how power works I could plug it into a 5V/2.4A USB-A charger and it would show the same thing.
this would be fine if you are worried about quality https://www.amazon.com.au/Belkin-WCB002auWH-Charger-iPhone-U…
ignore the 24w and fast charge text. it's just 2x 12W charger. (5V/2.4A)fast charging tends to reduces battery lifespan
Not anymore. Certain phone brands have ultrafast charging and increased battery cycles, longer life battery :)
My phone OnePlus Nord CE3 Lite has 67 watts charger, can recharge in 37 minutes from 0 and its battery is equipped with the 'Endurance' technology and firmware optimisations to help the battery last as long as possible. It's rated for up to 1600 charge cycles before significant deterioration.
I like these power towers. They have lots of AC points and plenty usb too, none are fast by todays standards: this one has 12 AC ports, 4 USB A ports, and 2 USB C ports firnexample https://amzn.asia/d/aWXKklI
I am afraid I only know where to buy a quick "slow cooker"…..
OP is asking for 2.5w max per port; my first thought was older Apple iPhone chargers, but they were 5w.
Are the batteries removable? You could look at a dedicated battery charger with programable charge rates, different settings etc for different chemistries?
Nah, not removable. One use is charging the phone at night. Can literally take all night, so 500mA is plenty. Other devices are things like ereader, headphones (have just had two sets of headphones batteries die suddenly), battery packs. Might try measuring the actual current draw and see if a 1A or more charger is actually fine.
https://www.laserco.com.au/power-accessories/chargers/wall-t…
4 USB Charging Ports: Equipped with two 2.4A and two 1.0A ports, this charger provides high-speed charging to both tablets and smartphones.
Aliexpress???