Order of Kilopi
Everytime I buy a new cellular phone or camera, the clerk tells me to load the battery for at least 8 hours for the first time before using.
However, I have never actually seen this written in the instruction manual.
Anyone know if this is really true? Thanks...
Banned
By all means - yes!
As battery technology has changed over the years, so have the procedures used to get the longest charge and the most life out of your battery. The one thing that hasn't changed, however, is the need to give it a good, solid, full charge right out of the box, followed by a full use to the point of exhaustion - one full cycle.
Whether that's 8 hours or not depends on the battery! If your cell phone has "fully charged" indicator, I'd watch it closely the first few times you charge it and pull it off the charger when it says it's fully charged.
Another fact that applies to all rechargeable batteries is that overcharging them will reduce their life, By how much depends on whether they're NiMH, NiCd, or Li-ion.
A myth is that fast-charging reduces the life of batteries. Well, it's not exactly a myth, as it's true - however, the amount of life that's reduced is so small it'll never be noticed by a human who is not using an electronic testbed, so fast-charge 'em if you got 'em.
Established Member
First full charge/discharge is just a leftover from old days. It doesn't apply to Li-ion batteries (which is about the only type you can find in any new camera/phone).Originally Posted by mugaliens
Li-ions are also more sensitive to over charging/discharging so batteries themselves contain electronics to prevent it. Keeping them connected to the charger forever isn't going to reduce the life time of the batteries, just the opposite actually...
Order of Kilopi
That is what I have gathered from the fact, that none of the doucmentation supplied with any of the phones/cameras I have seen recently don't speak of a first time loading procedure...
Order of Kilopi
Actually my cellphone DID have that 8-hour recommendation in its instructions.
Established Member
What about rechargables that are straight replacements for non-recharge batteries?
I bought a small digital camera that takes those, because I can always buy a non-recharge if the rechargables run out. But the rechargables don't last long, like a few months - say a dozen uses - and don't hold their charge. Advice on recharging those for long and reliable life?
I'm using AAs, marked NiMH (Nickel/Metal Hydride?) and a purpose-built charger, marked "for NiMH/NiCD batteries", that plugs straight into the wall, that the batteries clip into. I usually leave them in that overnight.
John
Established Member
Every rechargeable battery has a capacity (think of it as a fuel tank).
A 2500mah battery can only hold 2500mah (2.5amps for one hour)
Whatever current the charger delivers, once it has delivered 2500mah the battery is full. You can then disconnect it.
For example, if the charger delivers 250mah per hour, then it will take 10hours to charge the battery ( 250 x 10 = 2500 )
It's just simple math....
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(I fly big electric R/C planes.... we pull up to 100amps and the batteries can be fast-charged in one hour. But the principle is the same... if I pull 4000mah out of a battery, I have to put 4000mah back in or 4amps for one hour.)
Order of Kilopi
Yet apparently the simple math apparently did not apply to old technology batteries but just to the new Li-ion batteries...
Established Member
No, it applies to ALL rechargeables.
Works the same on ni-cad, ni-mh, li-ion and li-poly....
Order of Kilopi
Or rather, that simple math is a simplified version of the truth, which involves internal losses, per charge changes in the structure of the materials in the battery, etc. etc. etc.
The different types of rechargeables have different internal losses, different charging losses, different ways their internal structure changes over time and charging.
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Established Member
Battery lifetime is a rather complex affair and depend a lot on the chemistry of the battery in question. Since most rechargable devices use lithium ion batteries these days, I assume that is what you got.
When you buy a new Lithium-Ion battery, you should charge it before use, since it will probably have less than half charge, as the manufacturers would want to minimize deterioration between them and the consumer.
As storing a fully charged Li-ion battery at room temperature will cause about 20% deterioration a year, you too may want to discharge it to about 40-50% capacity if you are going to leave it unused for a longer time, as this will reduce the deterioration to about 5% a year, storing it in a cool place will reduce deterioration further, though temperatures below the freezing point of the electrolyte(around -40 celcius if I recall correctly) will damage the battery, so no storing it in dry ice or your basement mad scientist cryogenic lab... Storing it in a freezer at around 0 should be safe, at about half charge this will decrease the deterioration to about 2%, though it is probably not something you need to do, unless you plan on having batteries for several years in case the manufacturer discontinues them.
With lithium ion batteries it is ok to charge partly discharged batteries, but full discharges should be avoided as far as possible. Lithium Ion batteries will be damaged if discharged too much, so most batteries or devices using them have built in monitoring systems that will turn off the battery while there is still some charge left, so by full discharge I mean that the monitoring circuits indicate that the battery is empty. By the way, a battery in this state should be charged soon, as leaving it too long in this state may bring the cells in the battery below the minimum safe voltage for recharge, causing the safety circuits to prevent recharging, permanently disabling the battery. This also means that if you have batteries in long time storage, you should check them now and again, to keep the charge at around 40-50%.
Other than that... Well, I suppose you should avoid hitting, dropping or in some other way abuse the batteries physicaly, as lithium batteries are rather infamous for being unstable if mistreated, I suppose you have heard about people having their batteries blowing up or start burning...
Order of Kilopi
Once more: with a Li-ion battery which takes, say 2 hours to fully charge, you do not have to charge it the first time 8-10 hours, just 2 hours right?
Order of Kilopi
Yes, if a Lithium battery ever "puffs up" or swells, you should discard it and not recharge it. There are some ideas around about how to safely discard a lithium battery...
Established Member
You really do not have to think about this, all consumer electronics gear that employ batteries with lithium chemistry have to use charging regulators that will handle this, you could just leave the battery in the charger when not in use.
In fact, without these circuits such batteries would be impractical for general consumer electronics, as they would be like small incendiary bombs just waiting to blow up.
Though, if you use unprotected packs, like the ones used in RC models, you should keep them under observation while charging, and probably put them a place where there is nothing flamable within a stonesthrow or so, or invest in a good quality charger that will monitor the charging current, voltage and temperature
True, damaged lithium batteries should never be used or charged.
Well, if it is in the state you mentioned, it is probably quite unstable and liable to burst into fire or get very hot. Luckily most people that are not into RC, electronics or some specialized job or hobby where one encounter unprotected lithium batteries will probably not encounter this.
However, I think it is strange that I havent heard about some guy deciding it was to much of a bother to take his laptop battery pack to the nearest recycling point and so just dropping it in the trash, and the trash collector proceeding to crush the battery pack, resulting in it bursting into fire inside the car. Some of these batteries can have quite a bit of energy stored in them...
Order of Kilopi
Once a battery is charged, specificlly with a Li battery, the charger should shut down. Unlike Ni batteries, Li batteries do not recieve a trickle charge. This is also one of the reasons that you need to use a charger with Lithium batteries that is designed to be used with Lithium batteries.
Unlike Ni batteries, Li batteries do not have much of a "memory" and there is no need nor should you fully discharge them. Also they tend to not lose a charge if they are just sitting on a shelf (not plugged in) whereas Ni batteries pretty quickly lose 20 oe 30% of their charge if they are just sitting there.
The comments above are based on my experience with batteries for radio control electric powered aircraft, and documentation produced by manufacturers.
Newbie
Old NiCad type batteries needed charging for 8-24 hours when first charged, but they have hardly been used in small electronic devices (cellphones, MP3 players etc) for the last 10 years. Even so, the myth regarding the first charge lingers on and not just with end users but with some manufacturers who should know better.
Lithium-ion batteries are completely different and do not need the mega first charge.
First charge
The first charge isn't any different from the 2nd, third, or 74th charge with lithium-ions. These batteries have built in circuits to automatically turn charging on and off, so there is no point in doing all the normal rituals with charging it before using it, charging it for XX hours etc etc. If you have a lithium-ion, you're clear, no matter what the manual says. The XX hour first charge myth is left over from times with other battery types, and isn't relevant.
It should be noted however, that letting the device charge before you use it does allow you time to actually READ THE INSTRUCTIONS before you end up doing something you'll regret
Fully disharge/charge
Another myth, and a bad one. The only purpose ever in discharging a lithium-ion battery is to reset it's timer, so to display a more correct estimate for remaining battery time. Other than that, discharging your battery completely before recharging actually hurts the battery, as it's not designed to do so. Lithium-ions have a optimal life span when charged to about 3.92V, while 4.2V is max - and not recommended for extended periods of time. Also, charging a battery from 0% to 70% takes less time than to charge it from 70% to 100%, due to the charge method of such batteries.
Bottom line is that you should charge your battery often, and not max it out each time. It's better to charge it almost full many times than to fully charge it one time, in fact it might seriously increase the life span of the battery if you charge it randomly.
My experience and knowledge is based on working with these batteries every day and developing the best programs for the microprocessors that each one has built into it.
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