[Q] Dock design flaw? - Eee Pad Transformer Accessories

Hey,
Just thinking, anyone please correct me if I'm wrong, but as far as I know both the tablet and the dock have a Lithium-ion battery
From my knowledge, to keep lithium ion batteries in the best state you have to keep them between 20% and 80%, and not under/over charge them. The dock kinda seems to contradict this, because its constantly overcharging the tablet. This is extremely bad for the battery and greatly reduces the life span and capacity. Think of it as a laptop that you have in the socket 24/7, if you do this for half a year, the battery wont last for more then 30 mins. This, in a way, is resulting in the same problem.
Maybe this has been discussed before, but I couldn't find it, but isn't this a major design flaw? The dock should have some on/off charge switch.

It's not that simple. The Transformer, like every cell phone, laptop, and tablet using LiIon cells uses a charge controller chip that monitors charging current, pack voltage, pack temperature, discharge rate, and charge history to optimally control the power being fed to the battery from the charging input. The charge controller has a programmed hysteresis that keeps the battery from constantly charging (trickle charge) once it reaches its max capacity. Without a charge controller, the pack would eventually overheat and catch fire.
It is true that fully charged LiIon batteries will degrade in capacity over months to years. It's more damaging to the battery though to run it through a complete cycle (completely discharge). The best thing you can do for your battery without shelving the TF is to charge it every night to keep from unnecessarily running the battery down the next day.
In short, the Transformer can look after itself.
Also, this.

Thanks for your reply.
I might have used the wrong wording, I understand they have charge controllers to prevent the batteries from overcharging and exploding or catching fire. What I ment by overcharging was, charging it while the battery is already full, and undercharging - not charging it enough by letting it go into a deep discharge too often.
As stated in your link, "partial-discharge cycles can greatly increase cycle life, and charging to less than 100% capacity can increase battery life even further"
The dock keeps pushing it to 100%, and keeps it at 100% - reducing its battery life. Also, because you can not disable the dock charge, assuming you are constantly want to use the keyboard which I do, it will go into a deep discharge, also reducing the battery life of the dock. As often said, the best state for LiIon batteries is between 40% and 80%, this is hard to archive for both the dock and tablet due to it constant charging the tablet to full.
In order to preserve the best battery life, you must un-dock the tablet around 90% - and charge the dock whenever it reaches below 40% or so. Meeting both these requirements, while wanting to use the dock constantly seems like a burden. Not doing this, will rapidly decrease the capacity from my understanding.
Please correct me if I'm wrong though.

I don't see why people worry so much about this. It takes a few years for there to be any noticeable loss in battery life on lithium ion batteries, and even longer for it to become a significant burden.
It took me five years of daily usage of my old Toshiba laptop to wear down the battery to about half its original capacity, and it's still usable with only 2.5 hours of battery life. If we assume similar rules would apply to the Transformer, after 4-5 years you could still achieve a maximum of 8 hours on a single charge. If anything, by that time you'd be more concerned about how sluggish the device feels when compared to the newest tech, especially when browsing the web.

Related

[DISCUSSION] TouchPad Charging Recommendation & Battery Issues

So I have had mine sitting here all packaged up since tuesday.
And im looking to now actually open it and play with it,
Do you recommend I charge to full when off, or on? Perhaps run it dry and then charge it up?
You used to be told, Charge it for 8 hours before you use it...
That surely can't be true of todays rechargeable battery technology?
[Q] charging and battery damage
If I leave my touchpad on the touchstone charger for long periods and the touchpad is switched on will this damage the battery?
I know I have had laptops and always ran them of the mains and the battery has stopped holding a charge.
Cheers.
I assume that the touchpad has a charging circuit that stops it charging when the battery is full, but batteries will always fail after a while regardless. Lithium batteries are best charged often and not let run down too much in between.
Also, dson't let a lithium battery run down completely, you can significantly shorten its life doing that.
Troute said:
Also, dson't let a lithium battery run down completely, you can significantly shorten its life doing that.
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source? I thought lithium battery had no memory.
It's not a memory issue, running a lithium battery flat (deep discharging) has a physical effect on it where it will lose it's ability to recharge to as high a level as the previous charge. Each time this happens the battery loses more of it's ability to reach an effective voltage.
Don't take my word for it, do your own research, there's plenty of information out there it internet land.
alexhayuk said:
If I leave my touchpad on the touchstone charger for long periods and the touchpad is switched on will this damage the battery?
I know I have had laptops and always ran them of the mains and the battery has stopped holding a charge.
Cheers.
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The dev for Dr.battery's has a thread that states that leaving your Touchpad on the touchstone for long periods of time should not impact the battery. Due to it switching to powering the unit after its charged. Though he is doing some testing on that. Also his app should be updated soon for the Touchpad (available through preware). I am still going to contact HP to discuss this as well. I would hate to damage a non replaceable battery. Will update if I have any new info.
Sent from my HTC Sensation Z710e using xda premium
Troute said:
It's not a memory issue, running a lithium battery flat (deep discharging) has a physical effect on it where it will lose it's ability to recharge to as high a level as the previous charge. Each time this happens the battery loses more of it's ability to reach an effective voltage.
Don't take my word for it, do your own research, there's plenty of information out there it internet land.
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I have done my own research. That's why i don't think this is accurate.
If you have some proof please share.
Besides common aging, a Li-ion battery can also fail because of undercharge. This occurs if a Li-ion pack is stored in a discharged condition. Self-discharge gradually lowers the voltage of the already discharged battery and the protection circuit cuts off between 2.20 and 2.90V/cell.
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http://batteryuniversity.com/learn/article/how_to_prolong_lithium_based_batteries
Basically through normal use you can probably expect around 250-300 full charge cycles (partial charges only count as partial and add up with other partial charges to be a full cycle) in an average battery pack before it has degraded to 80% of it's original capacity. I don't see anything that point to full discharges being damaging. However storing it for longer periods of time fully discharged can affect life.
ambivalent-one I think the figure of 250-300 charge cycles you've pulled from that page refer to deep discharge cycle tests done by them, personally I'd be very unhappy with that kind of lifespan in a battery in regular usage. The same page you've posted http://batteryuniversity.com/learn/article/how_to_prolong_lithium_based_batteries shows a chart of charge cycles versus depth of discharge.
Table 2: Cycle life and depth of discharge
A partial discharge reduces stress and prolongs battery life. Elevated temperature and high currents also affect cycle life.
Charges - Depth of Discharge
500 - 100% DoD
1500 - 50% DoD
2500 - 25% DoD
4700 - 10% DoD
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As you can see a L-ion battery can be made to last nearly ten times longer by keeping the charge level up near max.
Quote from http://www.batterieswholesale.com/damaging_batteries.htm
The Li-Ion cell should never be allowed to drop below about 2.4V, or an internal chemical reaction will occur where one of the battery electrodes can oxidize (corrode) through a process which can not be reversed by recharging. If this occurs, battery capacity will be lost (and the cell may be completely destroyed)
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karan1203 if you reckon the information about deep discharge not accurate, can you provide the results of your own research that shows this?
Just let it die the first time, then charge when under 5%.
karan1203 said:
I have done my own research. That's why i don't think this is accurate.
If you have some proof please share.
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Click to collapse
Your research must've been incredibly basic in that case. The 2nd result I get when Googling "lithium batteries" gives me the wikipedia page which has a small amount of into on it:
http://en.wikipedia.org/wiki/Lithium-ion_battery
Look at the "Safety requirements" section for a start.
Also Google "lithium batteries discharge" returns some useful links.

[Q] When should I charge my phone?

To get the best battery life, when should I charge my phone? When the phone almost runs out of juice, or whenever I can (below 80%) ? Please help!
Deep discharges are bad, but so is spending lots of time at maximum charge.
I'd consider charging around when you hit 80% if it's convenient, but if you're expecting to be on battery for a while soon, top off whenever you want.
Discharging to 5-15% is bad for your battery longterm.
So to get the best battery, I should charge when it is $80 right?
Sent from my SAMSUNG-SGH-I777 using XDA App
kvl19 said:
So to get the best battery, I should charge when it is $80 right?
Sent from my SAMSUNG-SGH-I777 using XDA App
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There's no hard fast rule about 'exactly' when you should recharge it. Simply try and keep the phone from running < 20% a lot and never keep it always charged at 100%. If you get in the habit of charging in the 30-80% range, that would be best.
Basically throw out the old mentality of always using it as much as possible before recharging as lithium batteries simply don't work like the old nicad batteries from years past.
This phone uses a Li-Ion battery, and these batteries do NOT have any kind of "memory." Charge it whenever you want to. However, it's not really good to always keep it "topped off." (Deep discharges are also not good.)
If you are going to store the battery, drop it to 75%-50% charged first.
There are some things to consider, however:
If the phone's power circuit bypasses the battery when the battery is fully charge (instead of constantly pulling power from the battery while the battery is recharging), then leaving the phone plugged in is better than constant charge/discharge cycles. Based on the fact that this phone will work properly with NO battery attached when plugged in, this is probably a true statement (but I can't know for sure.)
Second, the phone itself might like to see the battery charged/discharged once in a while to calibrate the battery monitoring circuitry. (You never calibrate a li-ion battery - only the circuitry that monitors the battery.)
Here's a link with some interesting information:
http://batteryuniversity.com/learn/article/how_to_prolong_lithium_based_batteries
Take care
Gary
Got it. Thanks for all your information
A small note to add why you shouldn't 'keep' it above 80% (constant top offs and being left on the charger). In general when above 80% it's been found that lithium ion batteries have a 'higher state of activity'.
What that does to the battery is what it sounds like. Higher state of activity means higher wear and overall shorter lifespan.
That wear is easily seen in laptops. Many people have the habit of leaving them always plugged in while using and through the night, so they're always 'ready to go'. People who consistently do this to their laptops usually find after 1 year the battery life is noticeably shorter, 1 1/2 years 50% or so of 'new' capacity, and after 2 years looking at replacing the battery.
And I usually find a cheap deal on eBay for them, plus $50-75 for me. At least phone batteries are a bit cheaper.
Sent from my páhhōniē

is it better to charge the Tablet and Keyboard Dock separately?

Is it better to charge them separately?
From what I heard, the dock charges the Tablet. So if I charged with the two connected, the dock would charge, and it would in turn charge the Tablet...sounds kind of inefficient to me, and maybe even bad?
I usually charge my TF101 tablet from it's dock and have done so since September, perfectly fine and no negative impact on the battery. Just don't make a habbit of burning the batteries too low, like 1% before you charge.
My dock does drain a little faster after having gone through a bunch of heavy discharges but that's why I usually charge before I get to like 3% .
Spidey01 said:
I usually charge my TF101 tablet from it's dock and have done so since September, perfectly fine and no negative impact on the battery. Just don't make a habbit of burning the batteries too low, like 1% before you charge.
My dock does drain a little faster after having gone through a bunch of heavy discharges but that's why I usually charge before I get to like 3% .
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That's odd since it is recommended that you run the batteries down before charging them instead of putting it on the charger before it gets below 10%. Charging them without running the power down has a negative effect on the amount of charge it can hold.
That is not required anymore.The ideal charge level for these batteries is about 40%.
Charge cycles aren't a problem either so discharge is required once a month or even more.
These devices use LiPo and Co batteries.
For these, it is recommended NOT to fully let the battery discharge (unlike older batteries with memory effect).
It is however recommended to fully charge then fully discharge your battery ONCE when you first use it on order to calibrate the battery (ie: let the software learn what level means full and what level means empty)
Sent from my GT-I9100 using XDA App
eraursls1984 said:
That's odd since it is recommended that you run the batteries down before charging them instead of putting it on the charger before it gets below 10%. Charging them without running the power down has a negative effect on the amount of charge it can hold.
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You can check the link in my Sig. there is some info on recent batteries and calibration.
Yup, running it till it shuts off is mainly to calibrate the battery gauge. Most Lion batteries have auto shutoffs built into them to prevent discharging past the point of no return (which is why ebay batteries are so cheap, usually they lack this and other features, like temp sensors to kill the device before it melts)
As to charging both devices, i dont see how charging each together would harm anything aside from running more power through the dock might eventually wear it out? Honestly i dont think you have anything to worry about XD
But I can see the dock being discharged to zero so often. So far it has happened 4 times without me even knowing it since its often connected to the tablet. I wish there was a way to use the dock and disable the charging to the tablet.
Its better to have a few full discharge n full charge cycle for any new battery operated product to maximize the new battery capacity after a few cycles it will reach its peak capacity.
iceman127 said:
Its better to have a few full discharge n full charge cycle for any new battery operated product to maximize the new battery capacity after a few cycles it will reach its peak capacity.
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But I'm sure on many occasions just by the usage and nature of the dock that it will end up being drained to 0% quite often. I don't think my dock battery will survive too long -.-

dont over charge your battery

hi guys, just wanted to share a very handy device i have come across that i really like. I have an extra battery and cradle, however i dont trust the charging capabilities of the cradle once it reaches full charge. I know the device itself will slow down and trickle charge once it reaches full capacity, but in the cradle im afraid of overcharging the battery. anyhow, i began looking for a timing device to prevent this. I came across this item
http://www.amazon.com/Belkin-Conser...=1421085461&sr=1-1&keywords=belkin+timer+plug
it has a half hour setting, a 3 hour setting, or a 6 hour setting. i began to find myself using this, not only for the cradle, but when i go to bed at night. i connect it to my phone. 3 hour charge, then it shuts off. im surprised these arent more prevalent. in fact, belkin was the only one i could find, (short of those xmas light dial timers lol). let me know what you think
I've been using the cradle and extra battery for a while now. No issues. I swap it out daily(well until I got my PMA sticker)
Even before then, I noticed no issue with poor battery performance or life.
Here's some helpful info from Battery University website:
Simple Guidelines for Charging Lithium-based Batteries
A portable device should be turned off while charging. This allows the battery to reach the threshold voltage unhindered and reflects the correct saturation current responsible to terminate the charge. A parasitic load confuses the charger.
Charge at a moderate temperature. Do not charge below freezing.
Lithium-ion does not need to be fully charged; a partial charge is better.
Chargers use different methods for “ready” indication. The light signal may not always indicate a full charge.
Discontinue using charger and/or battery if the battery gets excessively warm.
Before prolonged storage, apply some charge to bring the pack to about half charge.
Over-discharged batteries can be “boosted” to life again. Discard pack if the voltage does not rise to a normal level within a minute while on boost.
Go here for more detailed info: http://batteryuniversity.com/learn/article/charging_lithium_ion_batteries

Note 7 and Lithium Batteries. An Educational thread.

I am seeing too many battery misconceptions. Let me clear them up.
STORAGE:
Lithium batteries like to sit around 50% for prolonged periods. If you need to power down your phone and store it, do it around 50-60%.
STATE OF CHAGE / BATTERY LEVEL
- It will NOT hurt to keep your phone on the charger. The charging circuitry cuts off power once the Cell hits 4.35 - 4.4v (If it did not, your battery would swell and heat up and then explode or catch on fire or both)
- It is MUCH more harmful to deplete the battery than it is to keep it full. Lithium batteries DO NOT like to go below a certain voltage depending on specific chemistry formulation.
For Example: Chevy Volt electric car Lithium battery is set to stay within 30% - 80%. They are limited to never exceed an SOC of 80% and never go below 30%. Source: https://en.wikipedia.org/wiki/Chevrolet_Volt
To expand on this. It is BETTER to keep the phone at 95% than it is to keep it at 5% for example. I personally would NOT want my battery falling low enough that it gives a low battery indication (usually around 15%). Usually I do not want it hitting 30%. That's a good rule imho.
CHARGE AND DISCHARGE CURRENT
Lithium batteries prefer to be charged slowly and discharged slowly. They do NOT like high charge and drain.
You guessed it. AVOID high charge scenarios such as Fast Charge. AVOID fast discharge scenarios such as gaming with high brightness etc.
TEMPRATURE
Lithium batteries do not like getting hot. They don't even like getting warm. Getting hot hurts it. Getting warm isn't as bad but it DOES degrade the total capacity over time.
Again, this is usually caused due to high charge or discharge scenarios.
It also ties in with Fast charge, wireless charge and especially wireless fast charge. Wireless charging is not efficient and energy as wasted as heat.
Personally I disable fast charge and do not use wireless charging. Good old USB Type C already charges quickly enough for me.
TLDR: Disable Fast Charge. Try to use USB Type C charging instead of wireless charging. Disable stuff you don't actually use. Try to keep power save on even if using it with very little power saving settings. Try to keep brightness at a reasonable level and not too high (This reduces AMOLED degradation too).
Remember: THE BATTERY IS NOT EASILY REPLACEABLE IN THE NOTE 7 !!!!!!!! Therefore the more you baby it, the longer it will hold it's charge and the lower the chance of the battery going bad.
My old Notes (Note 2 and Note 4) both still have VERY good original batteries because they were well taken of.
Good luck !
But I like fast charging and wireless charging lol
Ironic that when your phone is new, this is when the battery gets hot and used a lot. Perhaps with the water resistant phones we should update the firmware and restore the backup under water to keep the phone cool!
I will be sure to disregard just about everything in here. Guy is spreading false panic.
Actually "store mode" example: found in 7420 kernel source is 60-70% capacity. There are a lot of checks within source including battery swell etc. Don't fret about things, use your device. It's not as delicate as you may think. Who cares about the efficiency of wireless charging. Great if you've got it
90% won't keep beyond 2 years, just enjoy the thing !!
UN-recognized Developer of my SkyHigh Kernel v5.8.x powered SM-N920C
UpInTheAir said:
Actually "store mode" example: found in 7420 kernel source is 60-70% capacity. There are a lot of checks within source including battery swell etc. Don't fret about things, use your device. It's not as delicate as you may think. Who cares about the efficiency of wireless charging. Great if you've got it
90% won't keep beyond 2 years, just enjoy the thing !!
UN-recognized Developer of my SkyHigh Kernel v5.8.x powered SM-N920C
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My device arrived at 59% charge, ties in with what you say about storage.

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