Why does the battery take ages to charge?

[hotis300boy]

I kind of hate how the battery on this phone takes forever to fully charge, longer than any other phone I have owned, thought this was only on my first epic, but second is doing the same...why is this? any way to fix it?

 

[sole_elite_xx3]

Its cause of the battery it has

 

[ericdives]

Well it could be any number of things. And depends on what you think is a long time.

First, a slower charging battery tends to last longer over its lifetime than one that's constantly quick charged. In days of yore, if you used a car charger on a phone, the battery would usually charge quicker, but might end up not being able to hold a charge for long after doing this a lot.

Second, if your phone is having any one of the many battery issues that's coming to light (phone isn't sleeping, or the DRM service is running rampant), your phone is using a lot of power that could have gone towards charging the battery. So make sure you're following at least some of the battery advice I've collected from around the net.

Finally, going back to what you think is a long time: Anecdotally (could have been longer, no real stop watch, wasn't looking at the clock carefully), it took me around three hours with the phone powered off to go from a dead battery all the way to full charge. Not so bad, in my opinion, with a battery that might take a phone with light to no use 20+ hours to go from full to empty (again, all anecdotal, glancing at stats on the phone, was asleep most of that time).

From what I've read, if you're concerned about your battery, you can usually get Sprint to give you a new one if you go in and complain ... maybe even get a newer Epic from them!

 

[jamex]

Yea the battery charging is really slow. The palm pre charges really fast and it lasts about the same time as the epic that takes forever to charge.

 

[drewsg]

I use the charger supplied with the HTC Evo and my Epic charges much faster.

 

[jamex]

I hope you don't damage the device in the process.

 

[drewsg]

Been using it for a week and no damage to speak of

 

[Mike77]

Stock battery is larger then typical and a .7 amp charger is kinda low amp. Been using the pre's 1 amp. It is unlikely that a higher amp charger would hurt the device, the worst case scenario is possibly shorter battery life.

 

[amnchode]

The palm pre charges really fast and it lasts about the same time as the epic that takes forever to charge.

Keep in mind, the Pre also has a smaller battery (1150mah vs 1500mah). The bigger the battery, the longer it takes to charge to full capacity. That is if the charger was the same, but the Pre also uses a 1amp charger vs the .7amp we use now. Just adds that much more time. I am assuming Samsung is using a lower amperage charger to keep the battery from getting hot, but that is just a guess.

 

[bonanzabucks]

I use the stock battery charger and don’t have any complaints with the time it takes to charge. I’d say it takes about a couple of hours from almost empty to full for me. I’m coming from a Pre, which charged up really fast (even on an extended battery).

Speaking of batteries, I went to the Sprint store the other day for them to check mine out. All she did was take it out and look at it. She said it was fine. I have no reason not to believe her, but is that the normal procedure? Or do are they supposed to test it out electronically or something? This was at a store that had a repair center.

Also, regarding charging batteries, the woman working there told me I shouldn’t charge more than two hours and even leaving it overnight is bad for the battery. Is this true?

 

[xtn]

The amperage capacity of the charger does not determine the charging rate of a modern cell phone. Modern phones have charging circuits that define the amperage draw the phone will pull down. The amperage capacity of a charger is just that; a maximum design capacity.

xtn

 

[anon(47596)]

Charging through USB from a computer is only 500mA so even slower charging.

 

[Aero]

Its cause of the battery it has

no, it is because of the low MA charger. it comes with a 700 ma (.7 amp) charger whereas most smartphones come with a 1000 ma (1 amp) charger.

If your phone is drawing 100 ma, that leaves 600 left over to charge the battery on teh stock charger but 900 on a full one amp charger.

that is why a a typical charger will charge 50% faster than the samsung oem.

If you are in your car, and using gps, that means you are running GPS, 3g/4g, processor, gpu and screen full time and you could easily be pulling 600 ma off of your 1500 ma battery.

If you are pulling 600 and your charger is 700, changing to a one amp charge will charge you 400% faster.

The amperage capacity of the charger does not determine the charging rate of a modern cell phone. Modern phones have charging circuits that define the amperage draw the phone will pull down. The amperage capacity of a charger is just that; a maximum design capacity.

Actually in real the capacity of the charger does matter.

I can tell you for a fact that the Epic will draw 1000 ma for use and charging if connected to a 1000 ma charger.

I have three pieces. If I hook one discharged one to my 1000 ma chargers from my treos or htcs and one to the Epic stock 700 ma charger, the one on the 1000 ma charger will charge 30 to 50% faster easily --every time

 

[Aero]

I use the stock battery charger and don?t have any complaints with the time it takes to charge. I?d say it takes about a couple of hours from almost empty to full for me. I?m coming from a Pre, which charged up really fast (even on an extended battery).

Speaking of batteries, I went to the Sprint store the other day for them to check mine out. All she did was take it out and look at it. She said it was fine. I have no reason not to believe her, but is that the normal procedure? Or do are they supposed to test it out electronically or something? This was at a store that had a repair center.

Also, regarding charging batteries, the woman working there told me I shouldn?t charge more than two hours and even leaving it overnight is bad for the battery. Is this true?

There are some very nice and very informed sprint tech people. You met one who was not informed.

on a visual inspection of the battery they may check water damage (there is an indicator) and possibly date of manufacturer, and possibly corrosion on contacts. That is about as much as you can expect them to check.

Bt the info they gave you on charging is incorrect. LiIon batteries are best left plugged in.

 

[xtn]

Actually in real the capacity of the charger does matter.

I can tell you for a fact that the Epic will draw 1000 ma for use and charging if connected to a 1000 ma charger.

I have three pieces. If I hook one discharged one to my 1000 ma chargers from my treos or htcs and one to the Epic stock 700 ma charger, the one on the 1000 ma charger will charge 30 to 50% faster easily --every time

Oh I see. Then the charging circuitry in the Epic does allow for higher draw. I hadn't realized that. I had mistakenly assumed that since they shipped a lower ma charger, the phone was designed with a max draw at that level.

 

[scottmc129]

where does it say on the cable what MA it is? I have a BB Tour charger that was super quick. Does anyone know what Bberry uses for their charger cables? I will start using that for sure if this is the case.

 

[anon(47596)]

where does it say on the cable what MA it is? I have a BB Tour charger that was super quick. Does anyone know what Bberry uses for their charger cables? I will start using that for sure if this is the case.

To be clear, it's the transformer in the charger itself that specifies the voltage and amperage, not the cable itself. The output will be labeled on the charger itself. 5 volts and some amperage.

For those that buy those USB power plugs for the cigarette lighter plug in the car, keep this in mind. I've seen ranges from .5 to 1 amp output on those things.

 

[mister2quick]

So I have been using my extra Pre charger as my mobile charger and after reading this very informative post (thank you everyone!) I just have one clarification question: is it okay to charge the Epic with the Pre charger or is that going to cause bad battery wear and tear?

 

[jimmyz]

no, it is because of the low MA charger. it comes with a 700 ma (.7 amp) charger whereas most smartphones come with a 1000 ma (1 amp) charger.

If your phone is drawing 100 ma, that leaves 600 left over to charge the battery on teh stock charger but 900 on a full one amp charger.

that is why a a typical charger will charge 50% faster than the samsung oem.

If you are in your car, and using gps, that means you are running GPS, 3g/4g, processor, gpu and screen full time and you could easily be pulling 600 ma off of your 1500 ma battery.

If you are pulling 600 and your charger is 700, changing to a one amp charge will charge you 400% faster.



Actually in real the capacity of the charger does matter.

I can tell you for a fact that the Epic will draw 1000 ma for use and charging if connected to a 1000 ma charger.

I have three pieces. If I hook one discharged one to my 1000 ma chargers from my treos or htcs and one to the Epic stock 700 ma charger, the one on the 1000 ma charger will charge 30 to 50% faster easily --every time

Have you actually measured the current the phone draws? My understanding was that the phone only draws 600ma when D+/D- are shorted and 380 when they are not- thanks in advance

 

[IBNobody]

Have you actually measured the current the phone draws? My understanding was that the phone only draws 600ma when D+/D- are shorted and 380 when they are not- thanks in advance

Jimmyz's numbers are correct. They are what I measured with my handheld DMM at 40% and 80% charge.

Here is the FAQ I wrote up on the subject on XDA:
[FAQ][10/11/10] Samsung Epic USB/Wall/Charger FAQ - xda-developers

Aero,

While it would be nice if your 1A charger would charge the phone at 1A, that's not how it works. The phone regulates how much current it draws. Otherwise, when I hook it to my 3A capable USB charger (which I've modified to short D+ and D- together), it would blow up the battery. It does not do this. Instead, it draws 600mA.