IPad 2 baatery and charger

[smitty]

I know there's been a lot of discussion about this but I thought it might be good to get some real observations together. I went to bed and put the iPad 2 on charge at about 0200, at that time it was at ~31%. I got up this morning at 0700 and it was up to 85%. By 0830 it was up to 100%. I woke it up (smart cover) and did about 15 minutes of browsing ipf while still on the charger. That brought it down to 97%. I put it back to sleep and 20 minutes later it was back to 100%. BTW what happened to all the great usage stats from the iPhone 4? After about an hour's casual usage (without charging) it's now down to 84%.

It seems to me that it's pretty hard on batteries and is fairly slow to charge. I also had trouble believing that using it while on the charger would deplete the battery. Since I did not have an original iPad and have only my iPhone 4 for comparison, I'm not sure if I have a problem or not.

How does this stack up with what others are experiencing? Maybe we can do some real comparisons--Apples to Apples --and try to figure out what's normal and what isn't.

IPad 2 64 GiB + 3G with Smart Cover.

 

[twerppoet]

Use the included charger when you need rapid charging. It generally takes me about 4 hours (rough guess) for a 100% charge that way.

If you are charging from a computer or other source it will charge very slowly. The included charger supplies 10A of power. Most other charges, including your computer, only supply 2A. It will charge much more slowly off most computer USB ports. Older computers will only charge the iPad when the screen is off, and then very slowly indeed.

 

[Lifet1me]

If you got the Ipad real new i would use it until the battery goes emtpy, then make a full charge to 100% and a few hours more (the first times u load the percents arent what they show), then use it again until battery dies which will probably take 3/4 of the day and charge it over night again until 100% and a few hours more. 2-3 cycles of this will give the battery its full charge, after that u can charge it whenever you want to but a new battery needs this to work 100%

Always loading the battery on 55%, 34%, 70%, whatever in the middle, right from the beginning will only harm the battery and never give it its full capacy.

 

[twerppoet]

If you got the Ipad real new i would use it until the battery goes emtpy, then make a full charge to 100% and a few hours more (the first times u load the percents arent what they show), then use it again until battery dies which will probably take 3/4 of the day and charge it over night again until 100% and a few hours more. 2-3 cycles of this will give the battery its full charge, after that u can charge it whenever you want to but a new battery needs this to work 100%

Always loading the battery on 55%, 34%, 70%, whatever in the middle, right from the beginning will only harm the battery and never give it its full capacy.

No.

The only thing a full discharge and recharge does is recalibrate the battery charge indicator. It has no effect on the the batterie's life. The battery will not be harmed/damaged by failure to do so. More over, you can not fix a problem battery this way. If the battery is failing, the only alternative is to replace it. That's the reality of the new Lithium Ion batteries.

This kind of advice is a left over from the NiCad batteries that did have problems if they were not fully discharged/charged regularly.

That said, Apple recommends you do fully discharge and then recharge your battery once a month. As I said before, this is purely to maintain accuracy of the battery's charge indication.

 

[smitty]

Interesting! So far, the only comments have been about how to charge/discharge the battery. I was interested in comments and other's experience with how long a charge lasts and how long to charge.

I am using the supplied charger which I highly doubt puts out anything like 10 amps. More like 2 amps (it's a 10 watt charger not 10 amps). The standard USB 2.0 port puts out 500 ma (1/2 amp) at best--many won't even make that--so probably can't supply enough current to really charge the iPad at any reasonable rate. The statements about Li Ion batteries not needing all the charge/discharge stuff that NiCads needed is correct. Li Ion batteries do not have a memory issue. However, they do only have the ability to withstand a limited number of discharge/charge cycles. How many depends upon the batteries' specification and, AFAIK, Apple ain't revealing that number.

I was much more concerned that my iPad 2 was depleting the battery while in use but on the charger. This would seem to suggest that an operating iPad 2 pulls more than 2 amps. That sounds to me like something's very wrong and I'm trying to find out if it's a generic issue or specific to mine.

From the ifixit teardown report the battery is a 6,930 mAh battery. If the iPad 2 needed 2 amps, it would only run for ~3.5 hrs till it was flat dead. a 2 amp charger ought to be able to recharge it from dead in 6,930/2,000 = ~3.5 hrs.

So, how do these numbers compare with your experience? Have I got a unique problem or is this more like everyone else's experience?

Sent from my iPad using iPF

 

[iPadCharlie]

However, they do only have the ability to withstand a limited number of discharge/charge cycles. How many depends upon the batteries' specification and, AFAIK, Apple ain't revealing that number.

The answer is..... 1000

As posted on the Apple website Apple - Batteries - iPad

 

[twerppoet]

I am using the supplied charger which I highly doubt puts out anything like 10 amps. More like 2 amps (it's a 10 watt charger not 10 amps).

You are correct. My brain was not fully on.

And I did tell you my typical time to charge. Though since I rarely run my batter all the way down this is probably skewed on the short side, maybe as much as two hours for a full discharge. And I believe I said it was an impression. I've never actually timed it. It has certainly never failed to be fully charged after a night on the charger.

 

[smitty]

The answer is..... 1000

As posted on the Apple website Apple - Batteries - iPad

Thanks for that one, I had missed it. So, every night for about 2 1/2 years?

You are correct. My brain was not fully on.

And I did tell you my typical time to charge. Though since I rarely run my batter all the way down this is probably skewed on the short side, maybe as much as two hours for a full discharge. And I believe I said it was an impression. I've never actually timed it. It has certainly never failed to be fully charged after a night on the charger.

Thanks for the help. In the case I posted about, my "night" was only about 4 hours long, and it was down to ~31% when I started charging.

I am still curious about the battery depletion while on the charger. Has anyone else noticed that, either way?

Sent from my iPad using iPF

 

[jakerich]

The 1000 is for full cycles. Partial cycles don't count as much against that total. LiIon batteries don't like deep cycles, they work better if kept topped off (unlike NiCad). So if you deplete the battery every day almost to 0%, you'll see a degradation after about 2 1/2 years. If you recharge to 100% when it gets to 50%, that time stretches, theoretically, to 5 years, etc. However, another factor for LiIon is that the battery starts to degrade two years after manufacture, so the cycle limit is not the only thing going on.

However, the good news is that both degradations are very mild at first and there is a long, slow decay after it starts, not a steep drop. I would say the battery will outlast most of the devices in typical use.

 

[smitty]

However, the good news is that both degradations are very mild at first and there is a long, slow decay after it starts, not a steep drop. I would say the battery will outlast most of the devices in typical use.

Especially since they release a new "gotta have" model every year or so.

 

[DontUnderstandMyIpad]

Use the included charger when you need rapid charging. It generally takes me about 4 hours (rough guess) for a 100% charge that way.

Do you leave the iPad off during the charging?

Four hours seems to fast. When my iPad's battery is empty and I charge it through the original charger while still using the iPad at the same time, it takes around 12h, before the battery reaches 100% charge.

 

[Futurebird]

I do think that the battery loses charge faster on the iPad 2 than on the iPad 1. My husband and I left on a train trip with 100 each.. After about an hour I'm now at 87... He's at 95. Maybe I'm doing more battery intensive stuff? We are both connected via wifi... To me this is ominous... But maybe I'm over reacting.

 

[smitty]

I do think that the battery loses charge faster on the iPad 2 than on the iPad 1. My husband and I left on a train trip with 100 each.. After about an hour I'm now at 87... He's at 95. Maybe I'm doing more battery intensive stuff? We are both connected via wifi... To me this is ominous... But maybe I'm over reacting.

Yeah, I never had an original, so I don't know what battery life was like. I have heard that it was pretty good. With the 2 my experience has been that the 10 hour claim is a bit (perhaps quite a bit) of a reach.

Sent from my iPad using iPF

 

[twerppoet]

Use the included charger when you need rapid charging. It generally takes me about 4 hours (rough guess) for a 100% charge that way.

Do you leave the iPad off during the charging?

Four hours seems to fast. When my iPad's battery is empty and I charge it through the original charger while still using the iPad at the same time, it takes around 12h, before the battery reaches 100% charge.

Yes, I leave the iPad off for charging, most of the time anyway. I could be wrong about the 4 hours, it's an impression not a measure. I almost never run the iPad below 50% except when I'm intentionally doing the maintenance discharge/charge thing.

Even then, I've never plugged it in overnight like the OP and failed to have a full charge in the morning. I suppose I'll have to pay attention next time I do a maintenance cycle.

Im sorry to have given the impression I was reporting solid information.

 

[Futurebird]

I found out why my battery was going faster(I think) I had the 3G turned on, I'm not signed up for 3G but maybe just having it on in settings causes it to ping the cell towers wasting the battery. (??) Since I turned it off my iPad now seems to be losing charge slower than my husbands! I've been surfing the web on the couch for 1.5hours and it's still at 97%. now that's what I like to see!