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11 novembre 2011 5 11 /11 /novembre /2011 01:50

Electrochemistry

The three participants in the electrochemical reactions in a lithium-ion battery are the anode, cathode, and electrolyte.Sony VGN-TZ132/N Battery

Both the anode and cathode are materials into which, and from which, lithium can migrate. During insertion (or intercalation) lithium moves into the electrode. During the reverse process, extraction (or deintercalation), lithium moves back out. When a lithium-based cell is discharging, the lithium is extracted from the anode and inserted into the cathode.Sony VGN-TZ17N Battery

When the cell is charging, the reverse occurs.

Electrolytes

The cell voltages given in the Electrochemistry section are larger than the potential at which aqueous solutions can electrolyze, in addition lithium is highly reactive to water, therefore, nonaqueous or aprotic solutions are used.Sony VGN-TZ16N Battery

Liquid electrolytes in lithium-ion batteries consist of lithium salts, such as LiPF6, LiBF4 or LiClO4 in an organic solvent, such as ethylene carbonate, dimethyl carbonate, and diethyl carbonate. A liquid electrolyte conducts lithium ions, acting as a carrier between the cathode and the anode when a battery passes an electric current through an external circuit. Sony VGN-TZ18N Battery

Typical conductivities of liquid electrolyte at room temperature (20 °C (68 °F)) are in the range of 10 mS/cm (1 S/m), increasing by approximately 30–40% at 40 °C (104 °F) and decreasing by a slightly smaller amount at 0 °C (32 °F).

Unfortunately, organic solvents easily decompose on anodes during charging. Sony VAIO VGN-AR47G/E1 Battery

However, when appropriate organic solvents are used as the electrolyte, the solvent decomposes on initial charging and forms a solid layer called the solid electrolyte interphase (SEI), which is electrically insulating yet provides sufficient ionic conductivity. The interphase prevents decomposition of the electrolyte after the second charge. Sony VAIO VGN-AR520E Battery

For example, ethylene carbonate is decomposed at a relatively high voltage, 0.7 V vs. lithium, and forms a dense and stable interface.

A good solution for the interface instability is the application of a new class of composite electrolytes based on POE (poly(oxyethylene)) developed by Syzdek et al.Sony VAIO VGN-AR53DB Battery

It can be either solid (high molecular weight) and be applied in dry Li-polymer cells, or liquid (low molecular weight) and be applied in regular Li-ion cells.

Another issue that Li-ion technology is facing is safety. Large scale application of Li cells in Electric Vehicles needs a dramatic decrease in the failure rate. Sony VAIO VGN-AR54DB Battery

One of the solutions is the novel technology based on reversed-phase composite electrolytes, employing porous ceramic material filled with electrolyte.

Advantages and disadvantages

Note that both advantages and disadvantages depend on the materials and design that make up the battery. This summary reflects older designs that use carbon anode, metal oxide cathodes, and lithium salt in an organic solvent for the electrolyte.Sony VAIO VGN-AR550E Battery

Advantages

  • Wide variety of shapes and sizes efficiently fitting the devices they power.
  • Much lighter than other energy-equivalent secondary batteries.  Sony VAIO VGN-AR55DB Battery
  • High open circuit voltage in comparison to aqueous batteries (such as lead acid, nickel-metal hydride and nickel-cadmium). This is beneficial because it increases the amount of power that can be transferred at a lower current.
  • No memory effect.Sony VAIO VGN-AR630E Battery
  • Self-discharge rate of approximately 5-10% per month, compared to over 30% per month in common nickel metal hydride batteries, approximately 1.25% per month for Low Self-Discharge NiMH batteries and 10% per month in nickel-cadmium batteries.Sony VAIO VGN-AR64DB Battery
  • According to one manufacturer, lithium-ion cells (and, accordingly, "dumb" lithium-ion batteries) do not have any self-discharge in the usual meaning of this word.  What looks like a self-discharge in these batteries is a permanent loss of capacity (see Disadvantages). Sony VAIO VGN-AR65DB Battery
  • On the other hand, "smart" lithium-ion batteries do self-discharge, due to the drain of the built-in voltage monitoring circuit.
  • Components are environmentally safe as there is no free lithium metal.

Cell life

  • Charging forms deposits inside the electrolyte that inhibit ion transport. Over time, the cell's capacity diminishes.Sony VAIO VGN-AR660U Battery
  • The increase in internal resistance reduces the cell's ability to deliver current. This problem is more pronounced in high-current applications. The decrease means that older batteries do not charge as much as new ones (charging time required decreases proportionally).Sony VAIO VGN-AR690U Battery
  • High charge levels and elevated temperatures (whether from charging or ambient air) hasten capacity loss.Charging heat is caused by the carbon anode (typically replaced with lithium titanate which drastically reduces damage from charging, including expansion and other factors).Sony VAIO VGN-AR71ZU Battery
  • A Standard (Cobalt) Li-ion cell that is full most of the time at 25 °C (77 °F) irreversibly loses approximately 20% capacity per year. Poor ventilation may increase temperatures, further shortening battery life. Loss rates vary by temperature: 6% loss at 0 °C (32 °F), 20% at 25 °C (77 °F), and 35% at 40 °C(104 °F). Sony VAIO VGN-AR730E/B Battery
  • When stored at 40%–60% charge level, the capacity loss is reduced to 2%, 4%, and 15%, respectively.In contrast, the calendar life of LiFePO4 cells is not affected by being kept at a high state of charge.

Internal resistance

  • The internal resistance of standard (Cobalt) lithium-ion batteries is high compared to both other rechargeable chemistries such as nickel-metal hydride and nickel-cadmium, and LiFePO4 and lithium-polymer cells.Sony VAIO VGN-AR73DB Battery
  • Internal resistance increases with both cycling and age. Rising internal resistance causes the voltage at the terminals to drop under load, which reduces the maximum current draw. Eventually increasing resistance means that the battery can no longer operate for an adequate period.Sony VAIO VGN-AR74DB Battery
  • To power larger devices, such as electric cars, connecting many small batteries in a parallel circuit is more effective and efficient than connecting a single large battery.

Safety requirements

If overheated or overcharged, Li-ion batteries may suffer thermal runaway and cell rupture.Sony VAIO VGN-AR75UDB Battery

In extreme cases this can lead to combustion. Deep discharge may short-circuit the cell, in which case recharging would be unsafe.[58] To reduce these risks, Lithium-ion battery packs contain fail-safe circuitry that shuts down the battery when its voltage is outside the safe range of 3–4.2 V per cell.Sony VAIO VGN-AR790U/B Battery

When stored for long periods the small current draw of the protection circuitry itself may drain the battery below its shut down voltage; normal chargers are then ineffective. Many types of lithium-ion cell cannot be charged safely below 0°C.

Other safety features are required in each cell:Sony VAIO VGN-AR820E Battery

  • shut-down separator (for overtemperature)
  • tear-away tab (for internal pressure)
  • vent (pressure relief)
  • thermal interrupt (overcurrent/overcharging)   Sony VAIO VGN-AR830E Battery

These devices occupy useful space inside the cells, add additional points of failure and irreversibly disable the cell when activated. They are required because the anode produces heat during use, while the cathode may produce oxygen. These devices and improved electrode designs reduce/eliminate the risk of fire or explosion.Sony VAIO VGN-AR83S Battery

These safety features increase costs compared to nickel metal hydride batteries, which require only a hydrogen/oxygen recombination device (preventing damage due to mild overcharging) and a back-up pressure valve.

Specifications and design

  • Specific energy density: 150 to 250 W·h/kg (540 to 900 kJ/kg)  Sony VAIO VGN-AR83US Battery
  • Volumetric energy density: 250 to 620 W·h/l (900 to 1900 J/cm³)
  • Specific power density: 300 to 1500 W/kg (@ 20 seconds and 285 W·h/l)

Because lithium-ion batteries can have a variety of cathode and anode materials, the energy density and voltage vary accordingly.Sony VAIO VGN-AR84S Battery

Lithium-ion batteries with a lithium iron phosphate cathode and graphite anode have a nominal open-circuit voltage of 3.2 V and a typical charging voltage of 3.6 V. Lithium nickel manganese cobalt (NMC) oxide cathode with graphite anodes have a 3.7 V nominal voltage with a 4.2 V max charge. Sony VAIO VGN-AR84US Battery

The charging procedure is performed at constant voltage with current-limiting circuitry (i.e., charging with constant current until a voltage of 4.2 V is reached in the cell and continuing with a constant voltage applied until the current drops close to zero). Typically, the charge is terminated at 3% of the initial charge current. Sony VAIO VGN-AR85S Battery

In the past, lithium-ion batteries could not be fast-charged and needed at least two hours to fully charge. Current-generation cells can be fully charged in 45 minutes or less. Some lithium-ion varieties can reach 90% in as little as 10 minutes.

Charging procedure

Stage 1: Apply charging current until the voltage limit per cell is reached.Sony VAIO VGN-AR85US Battery

Stage 2: Apply maximum voltage per cell limit until the current declines below 3% of rated charge current.

Stage 3: Periodically apply a top-off charge about once per 500 hours.

The charge time is about three to five hours, depending on the charger used. Sony VAIO VGN-AR870EA Battery

Generally, cell phone batteries can be charged at 1C and laptop-types at 0.8C, where Cis the current that would discharge the battery in one hour. Charging is usually stopped when the current goes below 0.03C but it can be left indefinitely depending on desired charging time. Some fast chargers skip stage 2 and claim the battery is ready at 70% charge.Sony VAIO VGN-AR890U Battery

Top-off charging is recommended when voltage goes below 4.05 V/cell.

Typically, lithium-ion cells are charged with 4.2 ± 0.05 V/cell, except for military long-life cells where 3.92 V is used for extending battery life. Most protection circuits cut off if either 4.3 V or 90 °C is reached. Sony VAIO VGN-AR93S Battery

If the voltage drops below 2.50 V per cell, the battery protection circuit may also render it unchargeable with regular charging equipment. Most battery protection circuits stop at 2.7–3.0 V per cell.

For safety reasons it is recommended the battery be kept at the manufacturer's stated voltage and current ratings during both charge and discharge cycles.

Prolonging battery pack life

  • Depletion below the low-voltage threshold (2.4 to 2.8 V/cell, depending on chemistry) results in a dead battery which does not even appear to charge because the protection circuit (a type of electronic fuse) disables it.Sony VAIO VGN-AR93US Battery
  • This can be reversed in many modern batteries, especially single-cell ones, by applying a charging voltage for long enough to make the cell voltage rise above the low-voltage threshold; however this behaviour varies by manufacturer.
  • Lithium-ion batteries should be kept cool; they may be stored in a refrigerator.Sony VAIO VGN-AR94S Battery
  • The rate of degradation of Lithium-ion batteries is strongly temperature-dependent; they degrade much faster if stored or used at higher temperatures.
  • The rate of degradation of Lithium-ion batteries is also related to battery charge level; they degrade much faster when at 100% charge, than at lower charges.Sony VAIO VGN-AR94US Battery
  • Since batteries die if deep discharged (depleted) and since a battery has some self-discharge it is frequently recommended to store batteries at 40% charge level.

Multicell devices

Li-ion batteries require a Battery Management System to prevent operation outside each cell's Safe Operating Area Sony VAIO VGN-AR95S Battery

(over-charge, under-charge, safe temperature range) and to balance cells to eliminate SOC mismatches, significantly improving battery efficiency and increasing overall capacity.As the number of cells and load currents increase, the potential for mismatch also increases.Sony VAIO VGN-AR95US Battery

There are two kinds of mismatch in the pack: state-of-charge (SOC) and capacity/energy ("C/E") mismatch. Though SOC is more common, each problem limits pack capacity (mA·h) to the capacity of the weakest cell.Sony VAIO VGN-AW110J/H Battery

Safety

Lithium-ion batteries can rupture, ignite, or explode when exposed to high temperature. Short-circuiting a battery will cause the cell to overheat and possibly to catch fire. Adjacent cells may also then heat up and fail, in some cases, causing the entire battery to ignite or rupture. In the event of a fire, the device may emit dense irritating smoke.Sony VAIO VGN-AW11M/H Battery

Replacing the lithium cobalt oxide cathode material in lithium-ion batteries with a lithium metal phosphate such as lithium iron phosphate, improves cycle counts, shelf life and safety, but lowers capacity. Currently, these 'safer' lithium-ion batteries are mainly used in electric cars and other large-capacity batteryapplications, where safety issues are critical.Sony VAIO VGN-AW11S/B Battery

Lithium-ion batteries normally contain safety devices to protect the cells from disturbance. However, contaminants inside the cells can defeat these safety devices.

Recalls

In March 2007, Lenovo recalled approximately 205,000 batteries at risk of explosion.Sony VAIO VGN-AW11XU/Q Battery

In August 2007, Nokia recalled over 46 million batteries at risk of overheating and exploding. One such incident occurred in the Philippines involving a Nokia N91, which uses the BL-5C battery.

In December 2006, Dell recalled approximately 22,000 laptop batteries from the U.S. market.Sony VAIO VGN-AW11Z/B Battery

Approximately 10 million Sony batteries used in Dell, Sony, Apple,Lenovo/IBM, Panasonic, Toshiba, Hitachi, Fujitsu and Sharp laptops were recalled in 2006. The batteries were found to be susceptible to internal contamination by metal particles. Under some circumstances, these particles could pierce the separator, causing a short-circuit.Sony VAIO VGN-AW120J/H Battery

In October 2004, Kyocera Wireless recalled approximately 1 million mobile phone batteries to identify counterfeits.

Transport restrictions

In January 2008, the United States Department of Transportation ruled that passengers on board commercial aircraft could carry lithium batteries in their checked baggage if the batteries are installed in a device. Sony VAIO VGN-AW150Y/H Battery

Types of batteries affected by this rule are those containing lithium, including Li-ion, lithium polymer, andlithium cobalt oxide chemistries. Lithium-ion batteries containing more than 25 grams (0.88 oz) equivalent lithium content (ELC) are exempt from the rule and are forbidden in air travel.Sony VAIO VGN-AW160J/Q Battery

This restriction greatly reduces the chances of the batteries short-circuiting and causing a fire.

Additionally, a limited number of replacement batteries may be transported in carry-on luggage. Such batteries must be sealed in their original protective packaging or in individual containers or plastic bags.Sony VAIO VGN-AW170Y/Q Battery

Some postal administrations restrict air shipping (including EMS) of lithium and lithium-ion batteries, and products containing these (e.g. laptops, cell phones etc.). Among these countries and regions are Hong Kong, Australia and Japan.

Research

Researchers are working to improve the power density, safety, recharge cycle, cost and other characteristics of these batteries.Sony VAIO VGN-AW180Y/Q Battery

Solid-state designs  have the potential to deliver three times the energy density of typical 2011 lithium-ion batteries at less than half the cost per kilowatt-hour. This approach eliminates binders, separators, and liquid electrolytes. By eliminating these, "you can get around 95% of the theoretical energy density of the active materials." Sony VAIO VGN-AW190JAH Battery

Earlier trials of this technology ran into cost barriers, because the semiconductor industry's vacuum deposition technology cost 20–30 times too much. The new process deposits semiconductor-quality films from a solution. The nanostructured films grow directly on a substrate and then sequentially on top of each other. Sony VAIO VGN-AW190NAB Battery

The process allows the firm to "spray-paint a cathode, then a separator/electrolyte, then the anode. It can be cut and stacked in various form factors.

Lithium pharmacology refers to use of the lithium ion, Li+, as a drug. Sony VAIO VGN-AW190NBB Battery

A number of chemical salts of lithium are used medically as a mood stabilizing drug, primarily in the treatment of bipolar disorder, where they have a role in the treatment of depressionand particularly of mania, both acutely and in the long term. As a mood stabilizer, Sony VAIO VGN-AW190NCB Battery

lithium is probably more effective in preventing mania than depression, and may reduce the risk of suicide in certain bipolar patients. In depression alone (unipolar disorder) lithium can be used to augment other antidepressants. Lithium carbonate (Li2CO3), sold under several trade names, is the most commonly prescribed,Sony VAIO VGN-AW190YAB Battery

while the citrate salt lithium citrate (Li3C6H5O7) is also used in conventional pharmacological treatments. The sulfate salt lithium sulfate (Li2SO4) has been presented as an alternative. Lithium orotate (orotic acid) is sometimes marketed as a "safe" natural alternative with fewer side-effects than conventional lithium, yet caution must be taken with all of the active lithium salts.Sony VAIO VGN-AW190YBB Battery

Upon ingestion, lithium becomes widely distributed in the central nervous system and interacts with a number of neurotransmittersand receptors, decreasing norepinephrine release and increasing serotonin synthesis.

Medical uses

Lithium treatment is used to treat mania in bipolar disorder. Sony VAIO VGN-AW190YCB Battery

Initially, lithium is often used in conjunction with antipsychotic drugs as it can take up to a month for lithium to have an effect. Lithium is also used as prophylaxis for depression and mania in bipolar disorder. It is sometimes used for other psychiatric disorders such as cycloid psychosis and major depressive disorder.Sony VAIO VGN-AW190YDB Battery

Lithium possesses a very important antisuicidal effect not shown in other stabilizing medications such as antiseizures drugs.Non-psychiatric applications are limited; however, its use is well established in the prophylaxis of some headaches related to cluster headaches (trigeminal autonomic cephalgias), particularly hypnic headache. Sony VAIO VGN-AW220J/B Battery

An Italian pilot study in humans conducted in 2005–06 suggested that lithium may improve outcomes in the neurodegenerative disease amyotrophic lateral sclerosis.However, a randomised, double-blind, placebo-controlled trial comparing the safety and efficacy of lithium in combination with riluzole for treatment of amyotrophic lateral sclerosis failed to demonstrate any benefit from a combination therapy over riluzole alone.Sony VAIO VGN-AW230J/H Battery

Lithium is sometimes used as an augmenting agent to increase the benefits of standard drugs used for unipolar depression. Lithium treatment was previously considered to be unsuitable for children; however, more recent studies show its effectiveness for treatment of early-onset bipolar disorder in children as young as eight.Sony VAIO VGN-AW235J/B Battery

The required dosage (15–20 mg per kg of body weight) is slightly less than the toxic level, requiring blood levels of lithium to be monitored closely during treatment. To prescribe the correct dosage, the patient's entire medical history, both physical and psychological, is sometimes taken into consideration.Sony VAIO VGN-AW290JFQ Battery

The starting dosage of lithium should be 400–600 mg given at night and increased weekly depending on serum monitoring.

Those who use lithium should receive regular serum level tests and should monitor thyroid and kidney function for abnormalities. As it interferes with the regulation of sodium and water levels in the body, lithium can cause dehydration. Sony VAIO VGN-AW41JF Battery

Dehydration, which is compounded by heat, can result in increasing lithium levels. The reason why water is lost is because Lithium inhibits the action of antidiuretic hormone (ADH) which enables the kidney to reabsorb water from urine. This causes an inability to concentrate urine leading to consequent loss of body water and thirst.Sony VAIO VGN-AW41JF/H Battery

High doses of haloperidol, fluphenazine, or flupenthixol may be hazardous when used with lithium; irreversible toxic encephalopathy has been reported.

Lithium salts have a narrow therapeutic/toxic ratio and should therefore not be prescribed unless facilities for monitoring plasma concentrations are available.Sony VAIO VGN-AW41MF Battery

Patients should be carefully selected. Doses are adjusted to achieve plasma concentrations of 0.4 to 1.2 mmol Li+/L (lower end of the range for maintenance therapy and elderly patients, higher end for pediatric patients) on samples taken 12 hours after the preceding dose.Sony VAIO VGN-AW41MF/H Battery

Overdosage, usually with plasma concentrations over 1.5 mmol Li+/L, may be fatal, and toxic effects include tremor, ataxia, dysarthria, nystagmus, renal impairment, confusion, and convulsions. If these potentially hazardous signs occur, treatment should be stopped, plasma lithium concentrations redetermined, and steps taken to reverse lithium toxicity. Sony VAIO VGN-AW41XH Battery

The most common side effects are an overall dazed feeling and a fine hand tremor. These side effects are generally present during the length of the treatment, but can sometimes disappear in certain patients. Other common side effects, such as nausea and headache, can be generally remedied by a higher intake of water. Sony VAIO VGN-AW41XH/Q Battery

Lithium unbalances electrolytes; to counteract this, increased water intake is suggested.

Lithium toxicity is compounded by sodium depletion. Concurrent use of diuretics that inhibit the uptake of sodium by the distal tubule (e.g. thiazides) is hazardous and should be avoided. Sony VAIO VGN-AW41ZF Battery

In mild cases, withdrawal of lithium and administration of generous amounts of sodium and fluid will reverse the toxicity. Plasma concentrations in excess of 2.5 mmol Li+/L are usually associated with serious toxicity requiring emergency treatment. When toxic concentrations are reached, there may be a delay of 1 or 2 days before maximum toxicity occurs.Sony VAIO VGN-AW41ZF/B Battery

In long-term use, therapeutic concentrations of lithium have been thought to cause histological and functional changes in the kidney. The significance of such changes is not clear, but is of sufficient concern to discourage long-term use of lithium unless it is definitely indicated. Sony VAIO VGN-AW50DB/H Battery

Doctors may change a bipolar patient's medication from lithium to another mood stabilizing drug, such as valproate (Depakote), if problems with the kidneys arise. An important potential consequence of long-term lithium usage is the development of renal diabetes insipidus (inability to concentrate urine). Sony VAIO VGN-AW51JGB Battery

Patients should therefore be maintained on lithium treatment after 3–5 years only if, on assessment, benefit persists. Conventional and sustained-release tablets are available. Preparations vary widely in bioavailability, and a change in the formulation used requires the same precautions as initiation of treatment.Sony VAIO VGN-AW52JGB Battery

There are few reasons to prefer any one simple salt of lithium; the carbonate has been the more widely used, but the citrate is also available.

Lithium may be used as a treatment of seborrhoeic dermatitis (Lithium gluconate 8% gel). In addition, lithium has been shown to increase production of white blood cells in the bone marrow and might be indicated in patients suffering from leukopenia.

A limited amount of evidence suggests that lithium may contribute to treatment of substance abuse for some dual-disorder patients.Sony VAIO VGN-AW53FB Battery

Side effects

The average developmental score for the lithium-exposed group of children was 7–8 points lower than the control group (siblings), but well within the normal range of 100±15. Cognitive depression in adults is disputed.

Lithium is known to be responsible for significant amounts of weight gain.Sony VAIO VGN-AW70B/Q Battery

It increases the appetite and thirst ("polydypsia", potentially causing nephrogenicdiabetes insipidus), may cause more depression than before with suicidal thoughts and actions, and reduces the activity of thyroid hormone(hypothyroidism). It is also believed to affect renal function.Sony VAIO VGN-AW71JB Battery

Lithium is a well known cause of downbeat nystagmus. The nystagmus may be permanent or require several months of abstinence for improvement.

Lithium is also a teratogen causing birth defects in a small number of new born babies. If taken during a woman's pregnancy can cause her child to developEbstein's anomaly, a heart defect.Sony VAIO VGN-AW72JB Battery

Dehydration

Dehydration in patients taking Lithium salts can be very hazardous especially when combined with nephrogenic diabetes insipidus and thus polyuria. Low Natrium in water they drink may very quickly produce hyponatremia with its danger of toxic Lithium concentrations in plasma. Sony VAIO VGN-AW73FB Battery

Situation such as: preoperative fluid regimen (ECT) or otherwise fluid unaccessibility, warm water conditions, sporting events, hiking.

Overdose

Lithium toxicity may occur in persons taking excessive amounts either accidentally or intentionally on an acute basis or in patients who accumulate high levels during ongoing chronic therapy. Sony VAIO VGN-AW80NS Battery

The manifestations include nausea, emesis, diarrhea, asthenia, ataxia, confusion, lethargy, polyuria, seizures and coma. Other toxic effects of lithium also include coarse tremor, muscle twitching, convulsions and renal failure. Persons who survive a poisoning episode may develop persistent neurotoxicity.Sony VAIO VGN-AW80S Battery

Measurement in body fluids

Lithium concentrations in whole blood, plasma, serum or urine may be measured using instrumental techniques as a guide to therapy, to confirm the diagnosis in potential poisoning victims or to assist in the forensic investigation in a case of fatal overdosage.Sony VAIO VGN-AW80US Battery

Serum lithium concentrations are usually in the 0.5–1.3 mmol/L range in well-controlled patients, but may increase to 1.8–2.5 mmol/L in patients who accumulate the drug over time and to 3–10 mmol/L in victims of acute overdosage.Sony VAIO VGN-AW81DS Battery

Mechanism of action

Unlike other psychoactive drugs, Li+ typically produces no obvious psychotropic effects (such as euphoria) in normal individuals at therapeutic concentrations.

The precise mechanism of action of Li+ as a mood-stabilizing agent is currently unknown. It is possible that Li+ produces its effects by interacting with the transport of monovalent or divalent cations in neurons. Sony VAIO VGN-AW81JS Battery

However, because it is a poor substrate at the sodium pump, it cannot maintain a membrane potential and only sustains a small gradient across biological membranes.Li+ is similar enough to Na+ that under experimental conditions, Li+ can replace Na+ for production of a single action potential in neurons.Sony VAIO VGN-AW81YS Battery

Recent research suggests three different mechanisms which may or may not act together to deliver the mood-stabilizing effect of this ion.The excitatoryneurotransmitter glutamate could be involved in the effect of lithium as other mood stabilizers such as valproate and lamotrigine exert influence over glutamate, suggesting a possible biological explanation for mania.Sony VAIO VGN-AW82DS Battery

The other mechanisms by which lithium might help to regulate mood include the alteration ofgene expression.

An unrelated mechanism of action has been proposed in which lithium deactivates the GSK3? enzyme.  This enzyme normally phosphorylates the Rev-Erb? transcription factor protein stabilizing it against degradation.Sony VAIO VGN-AW82JS Battery

Rev-Erb? in turn represses BMAL1, a component of the circadian clock. Hence lithium by inhibiting GSK3? causes the degradation of Rev-Erb? and increases the expression of BMAL which dampens the circadian clock  Through this mechanism, lithium is able to block the resetting of the "master clock" inside the brain; as a result, the body's natural cycle is disrupted. Sony VAIO VGN-AW82YS Battery

When the cycle is disrupted, the routine schedules of many functions (metabolism, sleep, body temperature) are disturbed. Lithium may thus restore normal brain function after it is disrupted in some people.

Another mechanism proposed in 2007 is that lithium may interact with nitric oxide (NO) signalling pathway in the central nervous system, which plays a crucial role in the neural plasticity. Sony VAIO VGN-AW83FS Battery

Ghasemi et al. (2008, 2009) have shown that the NO system could be involved in the antidepressant effect of lithium in the Porsolt forced swimming test in mice. It was also reported that NMDA receptor blockage augments antidepressant-like effects of lithium in the mouse forced swimming test,Sony VAIO VGN-AW83GS Battery

indicating the possible involvement of NMDA receptor/NO signaling in the action of lithium in this animal model of learned helplessness.

Lithium treatment has been found to inhibit the enzyme inositol monophosphatase, leading to higher levels of inositol triphosphate.Sony VAIO VGN-AW83HS Battery

This effect was enhanced further with an inositol triphosphate reuptake inhibitor. Inositol disruptions have been linked to memory impairment and depression.

History

Lithium was first used in the nineteenth century as a treatment for gout after scientists discovered that, at least in the laboratory, lithium could dissolve uric acid crystals isolated from the kidneys. Sony VAIO VGN-AW90NS Battery

The levels of lithium needed to dissolve urate in the body, however, were toxic.Because of prevalent theories linking excess uric acid to a range of disorders, including depressive and manic disorders, Carl Lange in Denmark  and William Alexander Hammond in New York  used lithium to treat mania from the 1870s onwards though there are reports of its use in the form of spring waters to treat mania in Roman and Greek times. Sony VAIO VGN-AW90S Battery

By the turn of the century, this use of lithium was largely abandoned, according to Susan Greenfield due to the reluctance of the pharmaceutical industry to invest in a drug that could not be patented.

As accumulating knowledge indicated a role for excess sodium intake in hypertension and heart disease, lithium salts were prescribed to patients for use as a replacement for dietary table salt (sodium chloride).Sony VAIO VGN-AW90US Battery

This practise was discontinued in 1949 when reports of side effects and deaths were published, leading to a ban of lithium sales.

The use of lithium salts to treat mania was rediscovered by the Australian psychiatrist John Cade in 1949. Cade was injecting rodents with urine extracts taken from schizophrenic patients, Sony VAIO VGN-AW91CDS Battery

in an attempt to isolate a metabolic compound which might be causing mental symptoms. Since uric acid in gout was known to be psychoactive (adenosine receptors on neurons are stimulated by it; caffeine blocks them), Cade needed soluble urate for a control.Sony VAIO VGN-AW91CJS Battery

He used lithium urate, already known to be the most soluble urate compound, and observed that this caused the rodents to be tranquilized. Cade traced the effect to the lithium ion itself. Soon, Cade proposed lithium salts as tranquilizers, and soon succeeded in controlling mania in chronically hospitalized patients with them. Sony VAIO VGN-AW91CYS Battery

This was one of the first successful applications of a drug to treat mental illness, and it opened the door for the development of medicines for other mental problems in the next decades.

The rest of the world was slow to adopt this treatment, largely because of deaths which resulted from even relatively minor overdosing, including those reported from use of lithium chloride as a substitute for table salt.Sony VAIO VGN-AW91DS Battery

Largely through the research and other efforts of Denmark's Mogens Schou and Paul Baastrup in Europe, andSamuel Gershon and Baron Shopsin in the U.S., this resistance was slowly overcome. The application of lithium for mania in manic illness was approved by the United States Food and Drug Administration in 1970.Sony VAIO VGN-AW91JS Battery

In 1974 this application was extended to the use of lithium as a preventive agent for manic-depressive illness.

In 2009, Japanese researchers at Oita University reported that low levels of naturally-occurring lithium in drinking water supplies reduced suicide rates.[45] A previous report had found similar data in the American state of Texas.Sony VAIO VGN-AW91YS Battery

In response, psychiatrist Peter Kramer raised the hypothetical possibility of adding lithium to drinking water.

Lithium has become a part of Western popular culture. Characters in Pi, Premonition, Stardust Memories, American Psycho, and An Unmarried Woman all take lithium.Sony VAIO VGN-AW92CDS Battery

Sirius XM Satellite Radio in North America has a 1990s alternative rock station called Lithium, and several songs refer to the use of lithium as a mood stabilizer. These include: "Lithium Lips" by Mac Lethal, "Equilibrium met Lithium" by South African artist Koos Kombuis, Sony VAIO VGN-AW92CJS Battery

"Lithium" by Evanescence, "Lithium" by Nirvana, "Lithium and a Lover" by Sirenia, "Lithium Sunset", from the album Mercury Fallingby Sting,[48] "Tea and Thorazine" by Andrew Bird, and "Lithium" by Thin White Rope.Sony VAIO VGN-AW92CYS Battery

Use in 7 Up

As with cocaine in Coca-Cola, lithium was widely marketed as one of a number of patent medicine products popular in the late-19th and early-20th centuries, and was the medicinal ingredient of a refreshment beverage, 7 Up. Charles Leiper Grigg, who launched his St. Louis-based company The Howdy Corporation in 1920, invented a formula for a lemon-lime soft drink in 1929.Sony VAIO VGN-AW92DS Battery

The product, originally named "Bib-Label Lithiated Lemon-Lime Soda", was launched two weeks before the Wall Street Crash of 1929.[49] It contained the mood stabiliser lithium citrate and was one of a number of patent medicine products popular in the late-19th and early-20th centuries.Sony VAIO VGN-AW92JS Battery

The beverage was marketed specifically as a hangover cure. Its name was soon changed to 7 Up; all American beverage makers were forced to remove lithium in 1948.Sony VAIO VGN-AW92YS Battery,pack.co.uk/original-sony-vaio-vgn-aw93fs-battery-27294.htm" title="Sony VAIO VGN-AW93FS laptop battery">Sony VAIO VGN-AW93FS Battery,Sony VAIO VGN-AW93GS Battery,Sony VAIO VGN-AW93HS Battery,Sony VAIO VGN-AW93ZFS Battery,Sony VAIO VGN-AW93ZGS Battery,Sony VAIO VGN-AW93ZHS Battery

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