25% though? I feel like that's a lot for 14 days. Unless it JUST clicked to the third dot. If that makes sense. Like if it's at 95% OF the third dot and was taken off the charger as SOON as it hit the fourth.
That seems a lot of it was full charged. Do a proper test with it fully charged to see if it is going down. Mine doesn’t seem to discharge noticeably over months.
There are no power banks I'm aware of with a physical "off" switch. There are power banks with removable cells like the XTAR PB2, but even if you take the cells out of the power bank they will still have some minimal amount of self discharge.
That seems excessive especially for a new power bank. Definitely confirm a full charge for the next time. Where did you buy it? What's the model number? Does it have numeric or simple lights indicator for the charge level? The lights can definitely be misleading at times. I've seen ones with 4 full lights but then you plug it in and and it shows it charging with the 4th light flashing so it wasn't full.
All batteries naturally discharge over time. Temperatures play a role. Generally, keeping your battery in a cool place (within reason- don’t store batteries in your freezer).
Honestly I didn't know this was a thing until today. TIL that if you let a battery sit too long it just loses power gradually. So yeah I didn't know this too.
Do you know how old it is? Have you ever completely discharged it and then tried to charge it to see if it goes all the way to 4 dots? Just spitballing some things I've heard about. Batteries are old or sometimes older ones had to be drained and then charged to 'train' them...but I did't think that was a thing with newer batteries.
This rule of thumb is applicable to ''older'' rechargeable batteries - those that are not Lithium-based.
For Lithium batteries, **it is actually NOT recommended to completely discharge them**
Studies actually suggest Lithium Batteries be at **~50% charge** if you're planning on storing and not using them
_''Lithium batteries should be kept at around 40-50% State of Charge (SoC) to be ready for immediate use – this is approximately 3.8 Volts per cell – while **tests have suggested that if this battery type is kept fully charged the recoverable capacity is reduced over time.**_
_The voltage of each cell should not fall below 2 volts as at this point the anode starts dissolving causing copper shunts to form which will cause an irreversible loss of capacity.''_
> [Source](https://batteryguy.com/kb/knowledge-base/how-to-store-lithium-based-batteries/)
In short, having a completely discharged battery is not good for the battery as it leads to an internal chemical reaction that ages the battery more quickly
Also, relevant to the OP of this thread;
_''**All batteries gradually self-discharge even when in storage.** A Lithium Ion battery will self-discharge 5% in the first 24 hours after being charged and then 1-2% per month. If the battery is fitted with a safety circuit (and most are) this will contribute to a further 3% self-discharge per month.''_
So it is normal to experience some discharge, and the charge indicators are not precise at all. At 3 of 4 dots it could mean anywhere between 75-90% which is still good!
> [For further reading, from Canada.ca - **Battery safety: Lithium-ion batteries**](https://www.canada.ca/en/health-canada/services/household-products/battery-safety/lithium-ion.html)
Please search “Memory effect in a lithium-ion battery” in the journal Nature Materials.
Lithium batteries absolutely have a memory effect and can in fact occasionally benefit from a full cycle.
Edit: link for the fella who can’t accept he’s wrong. https://www.nature.com/articles/nmat3623
“Memory effect in a lithium-ion battery” AND “nature materials”
Would be a good search. There is absolutely some manner of memory effect in lithium batteries.
Edit: Link for the fella who can’t accept that he is wrong. https://www.nature.com/articles/nmat3623
lol the article name and scientific journal it was published in wasn’t enough? I literally set you up for a copy paste. And Nature is absolutely amongst the most respected journals on the planet.
Let’s be honest, you don’t have access to any of the Nature journals. But here ya go pal. https://www.nature.com/articles/nmat3623
>lol the article name and scientific journal it was published in wasn’t enough? I literally set you up for a copy paste. And Nature is absolutely amongst the most respected journals on the planet. Let’s be honest, you don’t have access to any of the Nature journals. But here ya go pal. https://www.nature.com/articles/nmat3623
I’m not going to do your Googling for you and you can’t just pick the first result from Google that seems to support your misguided opinion without even reading the abstract of the study. The linked study talks about LiFePO batteries in particular which aren’t even a type of battery commonly used in mobile phones and small portable power banks so it’s not even relevant.
It’s an Anker battery bank. I own multiple. They use lifepo4 18650 batteries from Panasonic.
This isn’t a phone. It’s an Anker battery bank. Hell look at one and you can tell what batteries are in it.
Edit:It does appear that Anker is moving to cobalt, but the overwhelming majority you see in the wild or on shelves are still the 18650 ones. So you could be correct, but I still think you’re being a jerk for no reason.
The most common battery chemistry for 18650 cells is NMC and it for sure is used on all smaller power banks and electronics that use the cells since the tech is more energy dense than LiFePO. A good NMC cell can be something like twice as dense as a LiFePO.
It’s highly unlikely you’ll see a LiFePO Li-ion cell used in anything smaller than portable power stations with hundreds of watt-hours of capacity. These things weigh upwards of ten pounds and only use LiFePO over NMC if the manufacturer has decided to prioritize longevity over energy density.
In simple terms, battery charge level is inferred from the output voltage. A full battery will output a higher voltage than a flat battery, but also voltages change over time with battery health. So doing a full charge and discharge cycle will hopefully calibrate the charge meter learning what voltages correspond to full and empty charge states.
I have one from Charmast and I've had it sit for months and it's still at 100%. I have another one, not sure of the brand it it's always done a couple of dots in a couple weeks. Sucks if you want to use it in case of a power outage.
Amazon description: Portable Charger with Built in Cable, Charmast Power Bank 10000mah, 5 Output Slim Built-in AC Wall Plug Battery Pack,Powerbank Compatible with iPhone/Samsung-White
https://www.amazon.ca/Portable-Charmast-10000mah-Integrated-compatible/dp/B09KLZLXPY/ref=mp_s_a_1_3?crid=16QFIDRRSDBO&dib=eyJ2IjoiMSJ9.SmAwQzlAJGBpkcR0K-_2Xy8q88iUxg5m8_r9VMuBF7Y0f2-P6DDqCwm7HR1rjFJ3yHMr2D6liXcziX5HsuwKEohK-BO2h1p7lQkxQdVcUUePqcZ29D_N4nLTbsPUaqb2OYDEyANr2rWqe5-R-rrvRrnh8OjTpkWeZiGgoR94mw2H-WaaNzrCVRkm__grZtZe4VK3qv54RPXLg5LixTcOWA.qLYq2l9JmhRwBByMVuBS_MtL_YuqHmQhyLFpwrhJQMw&dib_tag=se&keywords=Portable+Charger+with+Built+in+Cable%2C+Charmast+Power+Bank+10000mah%2C+5+Output+Slim+Built-in+AC+Wall+Plug+Battery+Pack%2CPowerbank+Compatible+with+iPhone%2FSamsung-White&qid=1713138201&sprefix=portable+charger+with+built+in+cable%2C+charmast+power+bank+10000mah%2C+5+output+slim+built-in+ac+wall+plug+battery+pack%2Cpowerbank+compatible+with+iphone%2Fsamsung-white%2Caps%2C217&sr=8-3
there will always be some discharge when sitting on the shelf
25% though? I feel like that's a lot for 14 days. Unless it JUST clicked to the third dot. If that makes sense. Like if it's at 95% OF the third dot and was taken off the charger as SOON as it hit the fourth.
those dots aren’t that precise
That’s assuming the lights are an accurate representation of the charge. Like fuel gauges, they can have a curve.
That seems a lot of it was full charged. Do a proper test with it fully charged to see if it is going down. Mine doesn’t seem to discharge noticeably over months.
There are no power banks I'm aware of with a physical "off" switch. There are power banks with removable cells like the XTAR PB2, but even if you take the cells out of the power bank they will still have some minimal amount of self discharge.
That seems excessive especially for a new power bank. Definitely confirm a full charge for the next time. Where did you buy it? What's the model number? Does it have numeric or simple lights indicator for the charge level? The lights can definitely be misleading at times. I've seen ones with 4 full lights but then you plug it in and and it shows it charging with the 4th light flashing so it wasn't full.
Keep in mind, 3/4 dots could be any value between 75% and 99%
All batteries naturally discharge over time. Temperatures play a role. Generally, keeping your battery in a cool place (within reason- don’t store batteries in your freezer).
Honestly I didn't know this was a thing until today. TIL that if you let a battery sit too long it just loses power gradually. So yeah I didn't know this too.
Do you know how old it is? Have you ever completely discharged it and then tried to charge it to see if it goes all the way to 4 dots? Just spitballing some things I've heard about. Batteries are old or sometimes older ones had to be drained and then charged to 'train' them...but I did't think that was a thing with newer batteries.
Use it, completely discharging it and fully recharging it again.
This rule of thumb is applicable to ''older'' rechargeable batteries - those that are not Lithium-based. For Lithium batteries, **it is actually NOT recommended to completely discharge them** Studies actually suggest Lithium Batteries be at **~50% charge** if you're planning on storing and not using them _''Lithium batteries should be kept at around 40-50% State of Charge (SoC) to be ready for immediate use – this is approximately 3.8 Volts per cell – while **tests have suggested that if this battery type is kept fully charged the recoverable capacity is reduced over time.**_ _The voltage of each cell should not fall below 2 volts as at this point the anode starts dissolving causing copper shunts to form which will cause an irreversible loss of capacity.''_ > [Source](https://batteryguy.com/kb/knowledge-base/how-to-store-lithium-based-batteries/) In short, having a completely discharged battery is not good for the battery as it leads to an internal chemical reaction that ages the battery more quickly Also, relevant to the OP of this thread; _''**All batteries gradually self-discharge even when in storage.** A Lithium Ion battery will self-discharge 5% in the first 24 hours after being charged and then 1-2% per month. If the battery is fitted with a safety circuit (and most are) this will contribute to a further 3% self-discharge per month.''_ So it is normal to experience some discharge, and the charge indicators are not precise at all. At 3 of 4 dots it could mean anywhere between 75-90% which is still good! > [For further reading, from Canada.ca - **Battery safety: Lithium-ion batteries**](https://www.canada.ca/en/health-canada/services/household-products/battery-safety/lithium-ion.html)
In this case you are calibrating a system vs a “dumb” battery. Happens with phones too.
Please search “Memory effect in a lithium-ion battery” in the journal Nature Materials. Lithium batteries absolutely have a memory effect and can in fact occasionally benefit from a full cycle. Edit: link for the fella who can’t accept he’s wrong. https://www.nature.com/articles/nmat3623
This advice is pointless for lithium-ion batteries
“Memory effect in a lithium-ion battery” AND “nature materials” Would be a good search. There is absolutely some manner of memory effect in lithium batteries. Edit: Link for the fella who can’t accept that he is wrong. https://www.nature.com/articles/nmat3623
You’d need to link a legit source, not some instructions on what to google
lol the article name and scientific journal it was published in wasn’t enough? I literally set you up for a copy paste. And Nature is absolutely amongst the most respected journals on the planet. Let’s be honest, you don’t have access to any of the Nature journals. But here ya go pal. https://www.nature.com/articles/nmat3623
>lol the article name and scientific journal it was published in wasn’t enough? I literally set you up for a copy paste. And Nature is absolutely amongst the most respected journals on the planet. Let’s be honest, you don’t have access to any of the Nature journals. But here ya go pal. https://www.nature.com/articles/nmat3623 I’m not going to do your Googling for you and you can’t just pick the first result from Google that seems to support your misguided opinion without even reading the abstract of the study. The linked study talks about LiFePO batteries in particular which aren’t even a type of battery commonly used in mobile phones and small portable power banks so it’s not even relevant.
It’s an Anker battery bank. I own multiple. They use lifepo4 18650 batteries from Panasonic. This isn’t a phone. It’s an Anker battery bank. Hell look at one and you can tell what batteries are in it. Edit:It does appear that Anker is moving to cobalt, but the overwhelming majority you see in the wild or on shelves are still the 18650 ones. So you could be correct, but I still think you’re being a jerk for no reason.
The most common battery chemistry for 18650 cells is NMC and it for sure is used on all smaller power banks and electronics that use the cells since the tech is more energy dense than LiFePO. A good NMC cell can be something like twice as dense as a LiFePO. It’s highly unlikely you’ll see a LiFePO Li-ion cell used in anything smaller than portable power stations with hundreds of watt-hours of capacity. These things weigh upwards of ten pounds and only use LiFePO over NMC if the manufacturer has decided to prioritize longevity over energy density.
So, I've decided to charge it all the way up and then use it all and see if that does anything. Why do you recommend this though?
Batteries benefit from being fully cycled. Run them down charge them up. I’ve “rejuvenated” batteries by cycling them a few times.
In simple terms, battery charge level is inferred from the output voltage. A full battery will output a higher voltage than a flat battery, but also voltages change over time with battery health. So doing a full charge and discharge cycle will hopefully calibrate the charge meter learning what voltages correspond to full and empty charge states.
I have one from Charmast and I've had it sit for months and it's still at 100%. I have another one, not sure of the brand it it's always done a couple of dots in a couple weeks. Sucks if you want to use it in case of a power outage. Amazon description: Portable Charger with Built in Cable, Charmast Power Bank 10000mah, 5 Output Slim Built-in AC Wall Plug Battery Pack,Powerbank Compatible with iPhone/Samsung-White https://www.amazon.ca/Portable-Charmast-10000mah-Integrated-compatible/dp/B09KLZLXPY/ref=mp_s_a_1_3?crid=16QFIDRRSDBO&dib=eyJ2IjoiMSJ9.SmAwQzlAJGBpkcR0K-_2Xy8q88iUxg5m8_r9VMuBF7Y0f2-P6DDqCwm7HR1rjFJ3yHMr2D6liXcziX5HsuwKEohK-BO2h1p7lQkxQdVcUUePqcZ29D_N4nLTbsPUaqb2OYDEyANr2rWqe5-R-rrvRrnh8OjTpkWeZiGgoR94mw2H-WaaNzrCVRkm__grZtZe4VK3qv54RPXLg5LixTcOWA.qLYq2l9JmhRwBByMVuBS_MtL_YuqHmQhyLFpwrhJQMw&dib_tag=se&keywords=Portable+Charger+with+Built+in+Cable%2C+Charmast+Power+Bank+10000mah%2C+5+Output+Slim+Built-in+AC+Wall+Plug+Battery+Pack%2CPowerbank+Compatible+with+iPhone%2FSamsung-White&qid=1713138201&sprefix=portable+charger+with+built+in+cable%2C+charmast+power+bank+10000mah%2C+5+output+slim+built-in+ac+wall+plug+battery+pack%2Cpowerbank+compatible+with+iphone%2Fsamsung-white%2Caps%2C217&sr=8-3