[el] lithium ion accu laten herleven

[Kr3Kr]

ik heb een probleempje: ik heb mijn telefoon [siemens s35i] in het water laten vallen, waardoor de accu voor ong. een half uur is kortgesloten. de telefoon doet het [mede dankzij een fohn] nog perfect, maar die accu is nu dus helemaal gaar.

toen ik het na het kortsluiten meette, stond er 0,2 volt op, ipv de gebruikelijke 3.6 het lijkt alsof de accu zichzelf steeds meer zelf bijlaadt, en hij gaat ook steeds minder bol staan... voltage is nu 1.7 volt


VRAAG:
is er iets dat het herleven van deze accu kan bevorderen, zoals peakladen, in de vriezer gooien, cycle laden[opladen ontladen, opladen etc etc. ???

een nieuwe accu kost namelijk 80 euro, en dat is net zo veel als ik voor de hele telefoon heb betaald.

bvd.

[Bandicoot]

Accu kost +/- 22 euro op een willekeurige computerbeurs.

En zelfs maar 18,15 euro bij [url="http://www.stuntprijzen.net/"]http://www.stuntprijzen.net/[/url]
/edit

[AcouSE]

Bron: [url="http://www.technick.net"]http://www.technick.net[/url]
[..]
The Li-ion typically discharges to 3.0V/cell. The spinel and coke versions can be discharged to 2.5V/cell. The lower end-of-discharge voltage gains a few extra percentage points. Since the equipment manufacturers cannot specify which battery type may be used, most equipment is designed for a three-volt cut-off.

Caution should be exercised not to discharge a lithium-based battery too low. Discharging a lithium-based battery below 2.5V may cut off the batterys protection circuit. Not all chargers accommodate a recharge on batteries that have gone to sleep because of low voltage.

Some Li-ion batteries feature an ultra-low voltage cut-off that permanently disconnects the pack if a cell dips below 1.5V. This precaution prohibits recharge if a battery has dwelled in an illegal voltage state. A very deep discharge may cause the formation of copper shunt, which can lead to a partial or total electrical short. The same occurs if the cell is driven into negative polarity and is kept in that state for a while. A fully discharged battery should be charged at 0.1C. Charging a battery with a copper shunt at the 1C rate would cause excessive heat. Such a battery should be removed from service.

Discharging a battery too deeply is one problem; equipment that cuts off before the energy is consumed is another. Some portable devices are not properly tuned to harvest the optimal energy stored in a battery. Valuable energy may be left behind if the voltage cut-off-point is set too high.

Digital devices are especially demanding on a battery. Momentary pulsed loads cause a brief voltage drop, which may push the voltage into the cut-off region. Batteries with high internal resistance are particularly vulnerable to premature cut-off. If such a battery is removed from the equipment and discharged to the appropriate cut-off point with a battery analyzer on DC load, a high level of residual capacity can still be obtained.

Most rechargeable batteries prefer a partial rather than a full discharge. Repeated full discharge robs the battery of its capacity. The battery chemistry which is most affected by repeat deep discharge is lead acid. Additives to the deep-cycle version of the lead acid battery compensate for some of the cycling strain.

Similar to the lead acid battery, the Li-ion battery prefers shallow over repetitive deep discharge cycles. Up to 1000 cycles can be achieved if the battery is only partially discharged. Besides cycling, the performance of the Li-ion is also affected by aging. Capacity loss through aging is independent of use. However, in daily use, there is a combination of both.

Het is mij niet helemaal duidelijk hoe je hem nu weer moet herladen, maar i.i.g. kun je hier dus lezen dat bij zeer diepe ontlading er een koper-kortsluiting ontstaat. Als je nu met de normale stroom zou laden kan er zeer veel warmte ontwikkelen, wat kan resulteren in een explosie (bekend effect bij Li-ion). Het ingebouwde beveiligingcircuit (zit in elke li-ion batterij) werkt hoogstwaarschijnlijk niet vanwege de lage spanning.