Can Laptop Battery Be Revived? Part 2: Result

Guess your battery must be dead. Buy a new one. Report back when you do.

Agreed!

In my limited experience, not only should he buy a new battery, but one from the original manufacturer. I bought a third party battery at about half the price, and it worked fine for several months (maybe a year). But now my computer shuts down when the battery indicates half-full charge. Your time and data are (presumably) much more valuable than the hassle of a cheap or poor battery.

Andy Germany (for whom I have great respect and gratitude) talks about a 10-year-old laptop with a battery that is still good. Maybe so, but that is hardly my experience. I've had 8 or more laptops over the years, and none had reasonable life of more than three years on the original battery. That included Lead-Acid, NiCad, NiMH, and Li-ion batteries. I've seen one case where a person left it plugged in for a year (never using the battery), and then went on a trip, only to find the battery only lasted an hour or less. Discharging the battery at least monthly does seem to help.

dkw: that's interesting. The life of batteries is something I've been looking into recently and two experts have, separately, told me that if you discharge any battery below a 50% state of charge, you irrepairablly damage it.

I've been wondering how best to treat my netbook battery to give it the longest life.

[PS I didn't subscribe to Part 1...I read the first couple of posts and decided leaving was best for all concerned as ranting at OPs is frowned upon. I see from Tornado's exchange earlier here, I was right in my assessment... .

How does someone subscribed to a thread find out a Part 2 thread has been inaugurated?]

Interesting. I have been told just the opposite, that batteries should be completely discharged from time to time to prolong life. I should do some research on this to get a better understanding, particularly on differences between maintaining Lithium Ion and Lead Acid batteries. Too much conflicting info to date.

I was told that 15 years ago about phone batteries. I was wondering if it's to do with the different technologies lead-acid/AGM vs. Li-on, NiCad etc.

I will ask my battery experts next time we speak ;o)

After having admitted that I know nothing about battery technology, I will now expound on the different types of battery technology.

It is my considered opinion that Ni-Cads should be discharged fully during each charge/discharge cycle.

Ni-Metal hydride batteries should be discharged fully during each charge/discharge cycle.

Li-on should not be discharged fully during each charge/discharge cycle and can be "topped off" without reducing their service life.

But, what do I know?

Laptop batteries should be stored at a charge level that equates with when the laptop says it now needs charging. Not empty, just low.

Discharging LA batteries below around 50% for long periods will damage them.....

I think the key word here is 'stored'. To me, that implies not being used for an extended period of time. Even my previous generation laptop is used at least a couple of times a month, to help others with problems on theirs... I do have several old laptops that are only rarely used for recovering old data; these I consider 'stored', but in most of those the battery has long since been discarded, and they are only used on line power.

It is a rare day indeed that I don't use this laptop, and since I fly almost every week, and work while I'm flying, I need a reliable battery! Even if I weren't flying regularly, I'd still want a reliable battery; where I live, power outages are fairly common (usually storms or drunken drivers hitting poles), and the laptop battery is my UPS.

The battery in your note book is of a type called Lion.

The battery pack has a circuit inside which should prevent discharging below a certain point and charging past a certain point, I forget the exact voltages.

Each individual cell's monitored during the charge / discharge cycles and though I am not a 100% sure all battery packs do this, during charging if some cells voltages reach the maximum allowed before others they are switched out of the charging circuit. this makes sure that individual cells do not become unbalanced during use. This gives you the best operating life and eventually due to usage and recharge cycles the capacity of the pack deteriorates and there is not much you can do to alter this situation.

"The battery in your note book is of a type called Lion."

You can't say that with such certainty! My current batteries are Lithium Polymer, which is not necessarily the same as Lithium Ion, although the chemistry may be similar. There were considerable differences between the various sources I researched on the topic...

Most, if not all, current laptop batteries do contain circuitry that monitors battery condition and maintains some form of battery history. I'm not sure exactly how that information is used by the battery and/or the computer, and I suspect that it varies from one brand to another. Apparently my third-party battery communicates in a different way than the original; last night the computer shut down without warning, when the LED indicator on the battery showed 4/5 of full charge. As soon as I can get to the store, I'll buy an original brand battery, even though it costs twice as much.

I'd love to know a lot more than I do about the circuitry inside these batteries, especially how much (if any) of the individual cell charging is controlled by the battery itself and how much is controlled by the circuitry in the computer. Any really knowledgeable experts on the forum?

You make a good point. Not only are urban myths rampant when it comes to batteries, but there are many different chemistries and control schemes out there.

Each one of these may require a different set of charging parameters and equipment.

I am certainly no expert, but I'd still suggest that any user follow the instructions of their specific computer/battery manufacturer. Remember, these are consumables and computer manufacturers plan to make money on their replacements.

"You make a good point. Not only are urban myths rampant when it comes to batteries, but there are many different chemistries and control schemes out there."

Precisely. I'd like to know more, and be more sure of what I know.

"...any user follow the instructions of their specific computer/battery manufacturer. Remember, these are consumables and computer manufacturers plan to make money on their replacements."

I'm one of the 'oldies' of which my kids despair - I read manuals!!! But I have yet to read much on battery maintenance. I doubt that the manufacturers make much on replacement batteries. I have seen about 9 laptops in the last 10 years, both business and personal. I have yet to buy a new battery, but have bought at least three new PSUs. Business laptops are replaced before the battery has got too bad. Personal laptops are wrecked by the kids before the batteries expire.

I've searched high and low for definitive battery discharging/charging information. I can't find any, either.

This is true of most battery powered equipment.

This leads to my main concern with battery powered hand tools. I store my batteries discharged, so I can't "just grab that drill" and go to work.

I find most replacement batteries are in the $100.00 USD range, which I think is excessive.

Cheers.

That's interesting, isn't it? Most manufacturers will encourage you to buy 'original equipment' batteries from them, but will never guarantee them, or take the blame if they expire prematurely. Nor will they tell you how to maximise battery life.

I have a good feel for manufacturing costs for many things, but not for batteries, but having just bought a new motorcycle battery, I agree that current prices seem excessive.

The original battery for mine is $129, and I agree that is excessive, but after my experience with shutdowns using a third party battery, I'm quite ready to pay the price. So far I've never lost more than 10 or 20 minutes' work with the unexpected shutdowns, but sooner or later...

I agree on the hand tool batteries. I commonly go a month without using my hand drill, and when I go to use it, it has about one minute of charge left.

The other advice I've been given recently is that it's better to store (at least AGM) batteries fully charged. I think it's to do with preventing sulphation and similar effects (or is that over charging?)

Sulfation occurs because Lead-Acid and AGM batteries use lead with H₂SO₄ as their electrolyte. BTW, my spell-checker does not like either sulfation or sulphation. When I Googled "battery sul", everything on the first page came up with the "f".

Since most other battery technologies use other electrolytes, they will have different problems.

I did fairly extensive testing with NiCads, and there was no doubt; they definitely lasted longer when fully discharged before recharging.

I've had a NiCd hand drill for quite a few years. Since it came with two battery packs, it was not a big problem to fully discharge one before charging it, and switch to the other while the first recharged. After something like 8 years, they didn't last as long, so I went to buy new batteries. They would have to be special-ordered, and a single battery pack was going to cost more than a new drill with two Ni-MH battery packs, so of course I bought the new drill. When I first tried them, they did hold a very good charge. But then I didn't use the drill for a month or two, and when I went to use it, both battery packs were essentially dead; almost completely self-discharged. So much for Ni-MH!

This last Christmas I got lucky due to an advertising error and was able to buy a new drill/screwdriver/reciprocating saw set at half price. This set uses Li-ion batteries (made in Korea) and so far, I am thrilled with them. The Li-ion battery pack weighs just 176 grams, compared to 466 grams for the Ni-MH pack, and they seem to be able to do about the same amount of work, with apparently no self-discharge! Major progress...

I just took a closer look. That Ni-MH battery pack is rated 9.6V at 2.2Ah, which is 21.1 Wh. The Li-ion pack is rated 12V at 16 Wh, so at roughly 36% of the weight, it has 76% of the rated storage capacity. In practice, after sitting for a month or two, the smaller battery actually holds more energy, since its self-discharge rate is so much lower.

Mechanically, I have been very happy with all three drills, but the smaller and lighter battery really makes this new one (and the screwdriver and saw as well) a pleasure to use (I'm a small fellow). For whatever it's worth, the first two were Makitas, and the new one is a Milwaukee.

The Lion battery packs for your drill has the same type of electronics on board to protect charge and discharge cycles.

You might notice that you will be happily drilling and it suddenly shuts down this is the protection circuit working.

With NiCds and Ni-Mh battery packs there is no electronic protection circuits so they can be over discharged quite easily, Up to the point after a fair amount of usage you will get cell reversal this does not improve the life of the cell in that it looses capacity so a recharge even if extended will not recoup the bad cell to the same as the others, from there it is a downward spiral to failure.

You are quite correct that a total discharge of NiCad battery is a good thing, unfortunately if the cells are not discharged individually you will have serious cell reversal of all but the last cell, this is not a good way to do it. {you will often see this recommendation but it is wrong} It is necessary to open up the pack and individually discharge the cells to get the best result. With Ni-Mh this effect is not pronounced .

I prefer Ni-Mh packs as they don't seem to leak the nasty green stuff that Ni-Cads do no memory effects and no electronic circuits as in Lion cells .I do power tool repairs and the amount of failed Lion batteries that come in for replacement is quite astounding.

As a matter of interest I have nickle cadmium wet cells as a car battery and am about to do this as most of the cells are only receiving a surface charge and the capacity is much diminished. Also these cells are about 25 years old and apart from this effect which is totally correctable they are still giving 90%

OK so it might be a Lithium polymer battery? The on board electronics do the same thing in detecting the cell voltages and the safe voltage range is virtually the same for both Lion and Lithium Polymer. The internal Resistance of Lion cells is higher than Li Po cells but the charging rate is still handled by the on board electronics with the same voltage limitations.

Unfortunately these types of battery packs suffer from a permanent loss off capacity if not used regularly due to the on board electrons draining the voltage below the recommended level, Also with regards to self discharge there is an optimum charge level for storage of 40 to 60% for Lion and Li Po cells.

So it is a bit of a trade off against storage and usage which causes the cells to deteriorate.

English Rose was asking how she might best look after her laptop battery I would recommend regular usage. Should have said that before.

Also as far as I know all the charging is controlled by the on board electronics which then tells the computer the state of charge.

The only reason being is that my batteries are as good as never in the laptops.......never get charged more than probably once a year or so. and rarely actually used.....very rarely.

Thanks all! Enlightening stuff.

It sounds like I'm not doing too badly by my laptop battery (Li-ion) as I generally run it from mains, but also wander off with it, occasionally getting to the "plug me in for heaven's sake" message. My power lead is a loose fit and the randomness of the contact means the battery gets "exercised" sometimes when I don't intend it :o)

I just had a "power cord dqngle" which I noticed when my self-set screen saver closed the screen. I've had my laptop for several years with no battery problems. I mostly use AC power, but the battery has always had a couple of hours available with no problem. My power tools, on the other hand, have shown dramatic effects. One summer when I was framing a house, I went through five Makita 9.6 v drill batteries. I think the cause of the losses was the high rate of charging, using the tool constantly, switching the batteries into the charger without cooling off first. The working conditions included high temps (ambient in the 90's plus no sunshade ). I wound up buying extra batteries after losing so many and charging in the shade after cooling off. This ended the slaughter.

As to recovering low life-time batteries, recharging (after cooling if necessary) after short automatic charge times, several times if necessary, has recovered almost half my defective batteries. The deep freeze method has worked for me, although I think it works better to stop short of "deep"" freeze: at least on the first try. This works as a starter to get a dead battery to take a small charge, then the multiple charge system increases the size of the charge. I am afraid that my newer tool batteries with the built-in computer controls are less amenable to recovery - though I've only lost one of six.

Some battery types have water in them, I personally cannot imagine that freezing the water (metal shrinking and water expanding it's size could damage something I feel), can in any way help to improve a battery's lifespan....... more than likely it will reduce it.....

Many people on the internet believe that freezing helps it would seem.....but you won't get me trying it out!

That's my 2 cents.....

I agree - freezing is for when you are ready to throw the battery away -but you can't 'cause the gummit won't let you - so you freeze it since you won't have to look at it in the freezer - then you remember that the water (or aqueous solutions) will be constantly changing their compositions as they cool, so you start pulling it back out of the freezer, checking it again, back to the freezer, etc. On a hot day, this behavior is actually positive, since you spend a lot of time in the freezer!

Freezing has worked for me on batteries ready to be thrown away (only).

Those batteries that you revive, are they'd lithium or metal hydride?