cell phone battery charge question

[TinderBox (UK)]

According to my user manual for the first charge even though the battery indicator is showing a fully charged battery you should leave it charging for a full 14 hours.

When the phone says the battery is fully charged is it not?

Thanks for the help.

 

[Russel]

Possibly a some type of forming charge?

http://www.cellpower.com/FAQs.cfm

Some lithium Ion powered consumer devices need to have the battery completely drained then charged in the device in order for the battery indicator to calibrate. That leads me to believe a couple of things. First, that the battery indicators are not very precise, and second that the battery level indicated is a somewhat course measurement.

All things being equal, I would follow the instructions of the manufacturer even if I didn't understand why they recommend charging for 14 hours for the first time.

 

[shadowjk]

I vote "remains from the nimh age"...

 

[Lite_me]

I am somewhat confused about Li-Ion cellphone treatment myself. I don't understand why (most cellphone) instructions state to do a 12~14 hr. initial forming charge, when everything I've read here about Li-Ion treatment is that they don't require conditioning. The only thing related to this is that after a few cycles, they may perform better. That's pretty much it.

The only other thing, aside from overcharging is not to completely discharge Li-Ion. But modern cellphone technology has this built-in. With my latest smartphone, I removed the battery to check it's voltage when the phone was close to shutting itself down form low battery power, and the battery still read just over 3.7v. I think this is a good, safe, setting.

I also removed immediately after a full charge, Green Light, with the phone off. It read 4.17v. Again, that's near perfect.

Getting back to that forming charge, I have no idea what/how current is still applied by the phones electronics after reaching full charge (green light). Does it trickle? My understanding is this is bad for Li-Ion. If it does not trickle, but monitors voltage and 'applies as needed' when left connected for extended periods, then it couldn't do a 'forming' charge.

So until I learn different, I'm going to continue my regime of not letting the battery get so low as to shut itself down, and to remove from charge upon Green Light , or even before but near it. I don't leave it plugged in unless it needs charging.

 

[Apollo Cree]

I've always thought companies give these complicated battery charging instructions at least in part so that when the crappy battery stops working due to manufacturing defects, some percentage of the users will say, "Gee, I guess I really should have done what the instructions said," instead of saying "What a piece of junk, this battery quit on me after just 3 months."

To me, the most proper reason for an initial long charge period would be if it does a slow trickle charge after the light goes out and thereby makes sure all cells in a battery are fully charged. This would help reduce the risk for reverse charging if one of the cells self-discharged more than the others in storage before being used by the customer.

 

[Lite_me]

To me, the most proper reason for an initial long charge period would be if it does a slow trickle charge after the light goes out and thereby makes sure all cells in a battery are fully charged. This would help reduce the risk for reverse charging if one of the cells self-discharged more than the others in storage before being used by the customer.

I'll admit I've never taken one of these proprietary, square/flat cellphone batteries apart, but I'm told it's a single battery. :shrug:

 

[Apollo Cree]

I'll admit I've never taken one of these proprietary, square/flat cellphone batteries apart, but I'm told it's a single battery. :shrug:

Good point on the cell phone batteries. Yes, if it's lithium and 3-4 V, it's probably a single cell.

 

[Russel]

After reading around on the net a little I noticed several articles imply that you should not believe the battery level indicator until the lithium ion cell has been cycled at least a couple times. Sometime referred to initializing the battery.

 

[TinderBox (UK)]

I think i will measure the battery voltage before charge and after the full charge indicator show, If the voltage is around 4.2 volts it should be charged if not i will let it charge a bit longer.

Any opinion is appreciated

Thanks

 

[herulach]

Android phones have a handy little app available that will give you the cell voltage temp etc.

Mine shows a green light at 4125mv, but carries on ramping all the way to 4195 where it seems to cut off.

What the extra 0.07V does is probably a bit questionable, but thats what it does over the next 5-6 hours after a full charge.

 

[march.brown]

I think i will measure the battery voltage before charge and after the full charge indicator show, If the voltage is around 4.2 volts it should be charged if not i will let it charge a bit longer.

Any opinion is appreciated

Thanks

.
I don't know whether the Li-Ion batteries used in Cameras are similar to those in mobile phones.

I have five batteries for my Panasonic camera and today I charged them fully ... Both my chargers measure 4.18 volts output ... After charging all my cells are reading 4.17 volts ... It would take literally for ever to get them up to the 4.18 volts of the charger ... I suspect that the voltage has been kept deliberately below 4.2 Volts in case some owners put their cells on charge overnight.

Perhaps this is what mobile phone manufacturers do, to try to avoid any battery fires etc.
.

 

[Lite_me]

Found this on Android Forums and thought I'd share.

Question... (in regards to the need to cycle and do an initial extended 'forming' charge on a new cellphone battery... as recommended by the manufacturer)

Aren't these Li-Ion Polymer batteries? I thought you didn't need to go through the full charge and discharge cycles like the old NiCad and NiMH batteries...

Reply...

That should be correct. It is really odd that the manufacturers recommend the charge and discharge cycles. Deep cycling a a Li-Ion battery will always hurt its charge capacity a little bit. Usually when a manufacturer recommends to fully charge and discharge one of these batteries it is so that the hardware can recognize the low and high voltages of the new battery over time to more accurately estimate the percentage of charge left. My hypothesis is that they are recommending that people do this so that the phone will be more accurate immediately at estimating the batteries level, and this really has nothing to do with conditioning the battery.

A Li-Ion battery is happiest (read: maintains its charge capacity best) when kept at cold temperatures and around 40-50% charge...

In other words the things you should avoid doing to your battery at all costs are:

1. Never let it get hot
2. Never full discharge it
3. Never keep it continuously fully charged on the charger

I have lived hard by these simple rules for many, many years and have the empirical evidence to prove to myself that they work. ie. a 5 year, 1 month old treo 650 battery that still lasted much, much longer than my setcpu'd hero or people with newer comparable treos. A 4 year old HP 12 cell battery that is still good for 4.5+ hours on a laptop.

Friends with identical cellphones and laptop/battery combinations could never understand why my batteries lasted so much longer, I tried to explain, but they just didn't understand how big of an impact these things make a battery's charge capacity.

Makes sense to me.

 

[TinderBox (UK)]

On the Apple website on the macbook battery care, they recommend you discharge the battery every couple of months to keep the battery in good condition and they say to keep the electrons flowing of something.

They also say to discharge the battery and then leave the macbook for 4 hours before recharging it.

 

[gsin123]

They say that so the internal Li-ion sell are balanced(all of them are fully discharged) so on the next charge all of them are fully charge.

 

[Russel]

I think that at 3.7 volts it is only one cell.

http://www.amazon.com/dp/B0028MBAXE/?tag=cpf0b6-20