# Why battery skips occur and how to fix them.



## sekine12

Battery Lifetime

Your battery is a lithium ion battery, it has a finite life. As the battery approaches the end of its life, the reported values for charge remaining will begin to skip some of the percentage range. This is evidenced by the four photos attached. One pair of photos shows a discharge cycle using an old battery, with approximately one year of reasonably heavy use. The second pair shows a discharge cycle using a battery which has roughly two months of use.

(Note, the two photos attached to this post are for the good battery. The two photos attached to the next post are for the bad battery)

Note that these shots include the percent discharge rate. The steep tail on the end of the good battery graph is the phone discharging with screen on during navigation on the highway. This is one of the heaviest use conditions we subject our phones to, and the discharge rate is about 30%, until it reaches 42% shortly before my battery died. This battery has a very low number of charge cycles, as I sad, about two months of use. However, it has sat in a drawer at 80% charge or so for the last year (it's was the SBF battery, just in case I do something dumb, and now that I've realized the daily driver is toast, it's my new daily battery) so that may be a 5% jump from 10% to 5%, time will tell. As I put more cycles on the battery I can expect that jump to grow.

On the other hand, the graph of the bad battery shows two jumps, each skipping a range of 10%. During these jumps, the discharge rate graph shows 55%/hr and 94%/hr jumps respectively. And, even more telling, the jumps occur during charging as well, see 182%/hr (that's outrageous, I don't have a 3.5 amp charger). So, in summary, as your battery gets old, its ability to discern its own charge becomes unreliable.

For more information regarding batteries, state of charge, charge reporting, calibration, etc, see this article: http://batteryuniversity.com/learn/article/the_battery_fuel_gauge . Do poke around the site and look at some of the other articles as well, they're well written and quite educational.

It is important to note that both of these batteries were purchased directly from Verizon, and are actually Motorola batteries. There are a massive number of off-brand batteries being sold online which look almost identical to the original batteries for our phones, but which do not perform as well. To add to the confusion, there's a revision of the BH6X battery which is designed for a different Motorola handset and does not play nice with ours. The solution to your battery skip problem: buy a new battery from Verizon, your old one is worn out. If you'd prefer to roll the dice and try buying one of the inexpensive batteries on Amazon, be my guest, but in my experience off brand batteries do not work nearly as well as original equipment. I don't buy in to merchandising "because it's better" (ie MosterCable for digital audio, unless you're trying to go a mile). But, in the case of batteries, every experience I've had indicates that it's best to go with a known good manufacturer for dependable results.

It is _not _the ROM.

The ROM may certainly effect battery life, if you notice a rapid, consistent drain on a brand new ROM, there's an issue going on. However, if you notice battery skips, it's not because the ROM is reading your battery incorrectly, it's because your battery can't tell the truth anymore, it's getting old and can no longer store 100% of its original charge capacity.

Please don't flood the dev threads anymore...


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## sekine12

Bad battery discharge images:


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## OsoRemby

Very informative

Sent from my SCH-I510 using RootzWiki


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## bobAbooey

Good info, thanks.


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## frankiedizzle87

A phone this new.... can the battery go bad that fast?

Sent from my Galaxy Nexus using Tapatalk


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## sekine12

Your GNex? Probably not. My DROID X? Yes.

Some where around 300 charge cycles lithium ion batteries seem to become unhappy, which equates to about a year of normal use on my phone, or two and a half years for me on my laptop. One charge cycle is 100% discharge and recharge, so 10% ten times counts as 1.

Also, there are case where your phone fails to read the battery correctly. This happens in the case of extremely large third party batteries, the DROID X will report incorrectly fast discharge (still not a skip) for pretty much anything over 2000mah.


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## SaurusX

Thanks for the explanation. It's pretty much exactly what I thought was occurring. I can only hope an pray that the battery skip talk will be excised from the dev threads. Somehow I doubt it, because once one person brings it up we get the next three pages being all battery talk.


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## an-dru

I had this too... Basically you all just need to say goodbye to the DX xP

The rezound is pretty sick! 

Sent from my ADR6425LVW using Tapatalk


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## deercreek

I just got a new battery built on 4/19/11 yesterday. I'm on my first charge so we'll see how it goes. It's already fixed two problems. My battery door had recently been hard to put on, and I've had a soft spot on my screen. It turns out the old battery was bulging somewhat. That was causing the extra pressure on the screen and back. I may be putting off a jump to the Rezound after all.

Sent from my DROIDX using Tapatalk


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## anrichardson

deercreek said:


> I just got a new battery built on 4/19/11 yesterday. I'm on my first charge so we'll see how it goes. It's already fixed two problems. My battery door had recently been hard to put on, and I've had a soft spot on my screen. It turns out the old battery was bulging somewhat. That was causing the extra pressure on the screen and back. I may be putting off a jump to the Rezound after all.
> 
> Sent from my DROIDX using Tapatalk


I ended getting the same build date on my new battery too and it was working great on my current CM7 Rom, but tried a few ICS roms then had a battery jump today when I was testing out AOKP b31 port. I was pretty pissed.

So I went back to my CM7 Rom and will be here for a long time. ICS roms are very sweet. But will stay away from them on my X.

May not be the Rom but the battery was working great before ICS rom and was actually last longer then the one my X originally came with.

Dropbox: 2GB of free cloud storage & get 500mb extra!!! http://db.tt/nQqMp4F


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## sekine12

anrichardson said:


> I ended getting the same build date on my new battery too and it was working great on my current CM7 Rom, but tried a few ICS roms then had a battery jump today when I was testing out AOKP b31 port. I was pretty pissed.
> 
> So I went back to my CM7 Rom and will be here for a long time. ICS roms are very sweet. But will stay away from them on my X.
> 
> May not be the Rom but the battery was working great before ICS rom and was actually last longer then the one my X originally came with.


Well, all I have to say about that is, see attached...

Gummy 3/30 build, went more than 24 hours (it was an all nighter for me, realized around 10am the next day the phone had finally died) - and that's the stock battery. Absolutely no complaints here. Where did you get your battery?

Also, the AOKP is definitely a work in progress... try a more finished ICS rom if you want something that will work well.


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## sekine12

I don't know why, but I absolutely could not get an image attached to the last post.


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## anrichardson

sekine12 said:


> Well, all I have to say about that is, see attached...
> 
> Gummy 3/30 build, went more than 24 hours (it was an all nighter for me, realized around 10am the next day the phone had finally died) - and that's the stock battery. Absolutely no complaints here. Where did you get your battery?
> 
> Also, the AOKP is definitely a work in progress... try a more finished ICS rom if you want something that will work well.


I will agree. Gummy wasn't an issue for me that I could see. But was referring that saying it's not the Rom, that it's the battery. I am on 4/12 cm7gb right now and no jumps.

I don't want to start another battery jump war, but using your thread instead of hijacking the Rom thread.

Dropbox: 2GB of free cloud storage & get 500mb extra!!! http://db.tt/nQqMp4F


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## sekine12

anrichardson said:


> I will agree. Gummy wasn't an issue for me that I could see. But was referring that saying it's not the Rom, that it's the battery. I am on 4/12 cm7gb right now and no jumps.
> 
> I don't want to start another battery jump war, but using your thread instead of hijacking the Rom thread.
> 
> Dropbox: 2GB of free cloud storage & get 500mb extra!!! http://db.tt/nQqMp4F


How long did you run the rom with the skips? And where did you buy the battery? Given a few full charge cycles you shouldn't have skips with a new OEM battery.


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## serx7

nice writeup, i should've looked this up @ batteryuniversity b4 since that's where i orig learned about battery longevity as a function of discharge depth (shallower depth of discharge being better than deep discharges).

the skips i see have always been consistent across ROMs and as of a few days ago i too am seeing big skips during the charging phase. just an hour ago it jumped from 26% to 60% over Battery Monitor's 5 min refresh interval. batt mV was 4021 @ 26% and 4056 @ 60%, so the readings are obviously whacked.

also, i've always seen 20+ hrs on VorteX by 15-20% batt remaining, with my pretty consistent usage patterns. starting a few weeks ago, that dipped to around 16 hrs, and during the week last week, has never been higher than 12-14 hrs.

i bought my DX certified pre-owned for $50 back in March '11, so i'm finding it hard to justify spending any appreciable amt of $ on a replacement battery. otoh i'm not eligible for an upgrade (early or otherwise) until Oct/Nov. wonder if my runtimes will be like 6 hrs by then


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## Drocka

Very helpful. Ive been getting battery skips like crazy on Gummy 1.0.2


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