Lithium Transfer Research Articles

Improvement of High-Rate Performance of LiFePO4 Cathode with through-Holed LiFePO4/Activated Carbon Hybrid Electrode Structure Fabricated with a Pico-Second Pulsed Laser

In order to improve high-rate performance of lithium iron phosphate (LiFePO4, LFP) cathodes, the LFP and activated carbon (AC) layers were coated on one side and the other side, respectively, of an aluminum (Al) current collector (producing the LFP/AC cathode), and then through-holes with the average diameter of 18-23 mm and opening rate of 0.44-0.64 % were formed in the LFP/AC cathode (producing the through-holed LFP/AC cathode). The cell fabricated with one through-holed LFP/AC cathode and two lithium (Li) metal anodes exhibited a significantly improved high-rate performance in the C-rate region of 50 to 100 C. The through-holed LFP/AC cathode was found to be superior in high-rate performance to a through-holed LFP/LFP cathode, where the LFP layers were coated on the both sides of an Al current collector, and a LFP/AC cathode having no through-holes. From the results obtained, it was found that, in a high-rate discharging process, AC layer is at first discharged because of its higher high-rate performance than the LFP layer and then energy (electrons) is (are) transferred by the difference in the electrode potential between the AC and LFP layers from the charged LFP layer to the discharged AC layer with the transfer of Li+ ions via through-holes from the AC layer to the LFP layer (i.e., the AC layer is charged again) and a series of such processes are repeated (Fig. 1). Forming through-holes in the LFP/AC cathode results in an improvement in its charging/discharging capacity and high-rate performance. Fig. 1 Schematic drawing of charging/discharging processes of the through-holed LFP/AC cathode. (A) Fully discharged condition, (B) fully charged condition, (C) first discharging of AC at high rate, (D) first open-circuit condition and electron and lithium transfer to charge the AC, (E) second discharging of AC at high rate, (F) second open-circuit condition and electron and lithium transfer to charge the AC. Figure 1

Anion-regulated solid polymer electrolyte enhances the stable deposition of lithium ion for lithium metal batteries

The adoption of lithium metal anodes, which are ideal for constructing batteries with high specific energy, is limited by dendrite growth and poor cycle performance. Herein, an anion-regulated solid polymer electrolyte based on in-situ-polymerized poly(ethylene glycol ether acrylate) is prepared for dendrite-free lithium metal batteries. According to the space-charge theory, the growth of lithium dendrites is effectively inhibited by the improved electric field of solid polymer electrolyte on the lithium anode side. And this solid system achieves a lithium transfer number of 0.63, excellent ionic conduction on 2.16 × 10−5 S cm−1 at room temperature), a wide electrochemical stable window (4.8 V vs. Li+/Li) and excellent cycle performance. The flexible batteries (LiFePO4 cathode/solid polymer electrolyte/lithium metal) are assembled to power a light-emitting diode at room temperature. We highlight the anion regulated polymer solid electrolyte, which shows great potential for solid lithium metal batteries and flexible batteries.

Development and Experimental Research on the Electromagnetic Induction Lithium Coolant Transfer Pump of a High-Power Space-Based NPP High-Temperature Cooling System

In the project of a modular submegawatt space-based thermionic NPP for the interorbital tug Gerkules, niobium alloy is used as the main structural material and isotopically pure lithium-7 is used as a coolant. To transfer lithium coolant, a series of electromagnetic induction pumps (EMP) have been designed, manufactured, and tested. The main requirement for EMPs is to ensure lithium transfer at high operating temperatures up to 900°C. This required high-temperature structural, magnetic, conductive, and electrical insulating materials. The design and technological features of the developed EMP are given. The tests were carried out in a pressure chamber as part of the lithium-niobium circuit simulating the NPP cooling system unit. The dependences of the EMP head-flow characteristics on the current strength and frequency, the temperature of transferred lithium, and other parameters are presented. The scatter of the same EMPs does not exceed 6%.

Chemical Oxidation of LiFePO4 in Aqueous Medium as a Method for Studying Kinetics of Delithiation

The kinetics of LiFePO4 oxidation by hydrogen peroxide in aqueous alkaline medium is studied with the use of potentiometric determination of lithium concentration in solution during delithiation. It is demonstrated that the lithium transfer through the reaction-product layer is controlled by diffusion. The activation energy and the diffusion coefficient of the species transferred in the solid phase during the chemical reaction of oxidative delithiation are determined and the parameters of this processes are analyzed.

Recovery of lithium from salt lake brine of high Mg/Li ratio using Na[FeCl4 ∗ 2TBP] as extractant: Thermodynamics, kinetics and processes

A systematic investigation on the extraction of lithium from salt lake brine with high Mg/Li using a novel extractant, Na[FeCl4∗2TBP]org, is reported with an emphasis on the extraction thermodynamics, kinetics and process. In liquid-liquid extraction, this extractant shows high separation factor of lithium/magnesium up to 178.4. Thermodynamic analysis indicated that the extraction is an exothermic process. However, when integrated with the kinetic effect, the lithium mass transfer increases at elevated temperature. The kinetics of lithium extraction by this extractant was investigated via a single drop column method. The magnesium, lithium concentration in brine, sodium, ferric concentration in organic extractant were studied, and a linear relationship was found between the rate of lithium transfer and the concentration of each component. The contribution of the formation/coalescence of organic extractant droplets, end-effect, to the lithium mass transfer was investigated. Perturbation at the brine/organic phases was found to promote lithium mass transfer during the rising step of droplets, mainly due to the low interfacial tension. Finally, a process was proposed to extract lithium ions from East Taijinaier salt lake brine and the stability of the new extractant was demonstrated by four extraction/stripping/saponification cycles. These results indicate that the present extractant was suitable for extracting lithium from brines with a high Mg/Li ratio.

The Influence of Ultrathin Amorphous ALD Alumina and Titania on the Rate Capability of Anatase TiO2 and LiMn2O4 Lithium Ion Battery Electrodes

Interface modification is a heavily investigated method of extending the lifetime of lithium ion batteries. While many studies have explored the effect of interface coating on the lifetime, the rate capability is often overlooked. In this study, the authors investigated the influence of ultrathin (<10 nm) atomic layer deposition (ALD) coatings of amorphous Al2O3 and amorphous TiO2. It is found that, on thin‐film anatase TiO2, the rate capability is unaffected by an amorphous TiO2 coating since it does not pose an additional impedance on the system, while Al2O3 coatings are detrimental for the rate performance due to the 1.5 × 1012 Ω cm resistivity toward lithium ions. A thicker than 2 nm ALD Al2O3 film is found to block lithium transfer completely, resulting in a purely capacitive film. Solvent oxidation is studied on thin‐film LiMn2O4. The authors demonstrate that both coatings can partially solve the solvent decomposition. However, the kinetic bottleneck posed by 1 nm Al2O3 is still greater than the uncoated LiMn2O4, leading to worsened rate capability. ALD TiO2 on the other hand can prevent most of the solvent decomposition, resulting in smoother electrodes. The absence of the decomposition layer and lithium conducting properties of the ALD TiO2 films results in an improved rate capability for the ALD TiO2 coated electrode.

(Invited) Development of a Superionic Conductor for High Power All-Solid-State Battery

Batteries has been widely used as energy source of mobile electronic devices and considered to be promising for large scale energy storage for electric vehicle and smart power grid due to their high energy density. Although high power density is required to regulate a large amount of electric power, the highest energy density battery, such as lithium ion batteries, generally offer lower power density than supercapacitors, because of slow ionic transport under the charge-discharge reactions. As the high rate capabilities of solid-state electrodes were confirmed, the rate determining steps that prevent their high power densities might be the ion transport in liquid electrolyte and/or at the liquid-solid interface. At high current condition, a concentration gradient is produced due to slow diffusion both of anions and cations of the electrolyte salts in solution, and lithium near the electrode region is consumed by the electrode reaction, this is well known as a solution phase diffusion limitation. In addition, reaction kinetics at the interface of liquid electrolyte / solid electrode is slow because of the (de-)solvation reactions of lithium ion that derives from a strong interaction between lithium ion and solvents. Since issues preventing the lithium ion batteries to be high power derive from the fundamental properties of liquid electrolyte, our strategy for high energy and power is to fabricate an energy storage device with solid electrolyte instead of liquids. Although the solidification of electrolyte has been investigated over the past few decades, none of the high power secondary systems have been actually realized. Low ionic conductivity of solid electrolytes (10-5 ~ 10-3 S/cm; three to one order of magnitude of lower than those of liquid electrolytes) causes high ohmic resistivity, resulting in poor electrochemical performance; none of the all-solid-state battery systems could operate at the high current density region where solution phase limitation occurs in lithium ion battery systems, therefore, the advantage of solid configurations have not been clarified experimentally. In this study, we reported a superionic conductor of Li9.54Si1.74P1.44S11.7Cl0.3 the materials group, Li10GeP2S12. It exhibits the ionic conductivity of 25 mS cm-1 at room temperature. The wide three dimensional distributed lithium in the framework of this crystal has been clarified using careful structural analysis using neutron diffraction technique. Such a high ionically conducting solid may improve the power characteristics of the all-solid-state battery. Therefore, here we clarify the rate characteristics of an all-solid-state battery using the developed solid electrolyte and compare the performance with that of a lithium-ion battery with a standard liquid organic electrolyte of 1M LiPF6 in EC:DEC. The rate capability of all-solid-state batteries was superior to that of lithium ion battery using liquid electrolyte although the configuration of batteries were same for each systems except for electrolytes. The results of high rate capability of all-solid-state battery could be summarized as below: (Low temperature) A significant difference in the discharge profiles of the solid-state and liquid electrolyte systems was evident; while the all-solid-state battery exhibited large charge-discharge capacity at current densities of 0.03 mA cm-2, large voltage drops were observed for the liquid electrolyte battery. (Room temperature) Differences in rate characteristics between the solid-state and lithium ion batteries are clearly indicated by the rate dependence of the discharge capacities. Discharge capacity of the liquid electrolyte battery decreased rapidly at a current density of 30 mA cm-2 (45 C), although no differences in discharge capacities of the solid-state and liquid electrolyte batteries were found in the low current density region of 0.06 mA cm-2 (0.09 C) to 20 mA cm-2 (30 C). (High temperature) The performance of lithium ion battery and all-solid-state battery were evaluated at high temperature 100 °C. The lithium ion battery could not function due to thermal instability of the LiPF6-based liquid electrolyte19. In contrast, the present all-solid-state battery exhibits the excellent performance at high temperature owing to good thermal stability of solid electrolyte. The advantages of the all-solid-state battery are discussed using electrochemical evaluation techniques: (1) simple lithium transfer at the electrode / electrolyte interface with low activation energy that reduces the charge-transfer resistance at low temperatures. (2) High lithium concentration and high lithium-ion transport number prevent a concentration gradient under high rate current conditions, promoting a high rate performance. (3) Thermal stability of solid electrolyte allows to exhibit ultrahigh rate discharging performance at high temperature where lithium ion battery could not be operated. These results showed the experimental evidence of high power in an all-solid-state battery.

Electrochemical Investigation of Thermodynamic and Transport Phenomena in LP30 Electrolyte with Various Concentrations of Conducting Salt

The electrification of mobility has a strong potential to reduce fuel consumption and CO2emissions. This alternative to combustion engines, however, is hampered by battery systems still insufficient in terms of energy, power and lifetime. Therefore it is important to investigate and understand the electrochemical processes and mechanisms that can maximize the power-to-energy ratio. The electrolyte plays an important role for the efficient operation of the battery. For example, electrolytes with low lithium-ion transport numbers and salt diffusion coefficients cause large concentration polarizations during operation of Li-ion batteries. This leads to poor high-rate performance, unwanted side reactions and ageing. It is therefore important to characterize and model the transport phenomena in electrolytes under battery operation conditions. There are numerous experimental methods that can be used to characterize the thermodynamic and transport phenomena in electro-diffusion processes (e.g. NMR, Raman spectroscopy, etc.), but the electrochemical methods are more powerful, as they can mirror the relevant working processes occurring in a battery. In the presented work, the electrolyte characteristics such as viscosity, conductivity, diffusion coefficients of lithium ions and transfer numbers are determined for various LiFP6concentrations. Conductivity was measured by alternating current technique (PEIS and test cell with Pt-electrodes); the transfer numbers were obtained from the diffusion technique (concentration cell) and the diffusion coefficient was determined by the rotary disk electrode method and also calculated from conductivity measurements. Additionally, the temperature dependence of the studied properties was taken into account. The results were further used for the modelling of the mass transport processes in the real cell. The analysis of mass transport phenomena over a range of salt concentrations will be shown and discussed. Acknowledgement The authors would like to thank the Austrian Federal Ministry for Transport, Innovation and Technology (bmvit) and the Austrian Research Promotion Agency (FFG) for their financial support.

Numerical Analysis on Lithiation and Delithiation Kinetics of Composite Silicon-Graphite Electrodes

To study electrochemical lithiation and delithiation kinetics in silicon-graphite composite anode for lithium-ion batteries, a discrete diffusion particle model (DDPM) is developed and validated. Our recent study indicates conventional single-particle model shows limited representation of mixed chemistry. This model solves solid-phase lithium diffusion dynamics and transfer kinetics in a discrete diffusion particle system, which can be used to address the effects from composition of active particles of different chemistry, particulate morphology and size distribution. Half cells are built and tested for modeling parameter identification and validation. Tests include constant-current / dynamic charge and discharge at various temperatures. Results show well captured characteristics of inhomogeneous use of different materials, especially at state of charge region close to 0% and 100%. Comparison between modeling and testing suggests the model gives a reasonable accuracy and could be used to quantify the impacts of electrode design parameters, providing insights for improving the performance of the mixture negative electrodes.

Three-dimensionally scaffolded Co3O4 nanosheet anodes with high rate performance

Advances in secondary batteries are required for realization of many technologies. In particular, there remains a need for stable higher energy batteries. Here we suggest a new anode concept consisting of an ultrathin Co3O4 nanosheet-coated Ni inverse opal which provides high charge–discharge rate performance using a material system with potential for high energy densities. Via a hydrothermal process, about 4 nm thick Co3O4 nanosheets were grown throughout a three-dimensional Ni scaffold. This architecture provides efficient pathways for both lithium and electron transfer, enabling high charge–discharge rate performance. The scaffold also accommodates volume changes during cycling, which serves to reduce capacity fade. Because the scaffold has a low electrical resistance, and is three-dimensionally porous, it enables most of the electrochemically active nanomaterials to take part in lithiation–delithiation reactions, resulting in a near-theoretical capacity. On a Co3O4 basis, the Ni@Co3O4 electrode possesses a capacity of about 726 mAh g−1 at a current density of 500 mA g−1 after 50 cycles, which is about twice the theoretical capacity of graphite. The capacity is 487 mAh g−1, even at a current density of 1786 mA g−1.

Synthesis of Polypyrrole Encapsulated Tin Oxide Nano Powder By Spontaneous Co Precipitation and Evaluating for Lithium Ion Battery Anode Material

The tin oxide has been prepared by spontaneous co precipitation method. Pyrrole has been polymerized and encapsulated on to the tin oxide nano particle using FeCl3 as a polymerizing agent. The prepared material has been well characterized to understand the structural and morphological nature. XRD study confirms the nature of crystal is tetragonal and the having space group P42/mnm, the SEM images shows the flaky formation of polypyrrole consisting tin oxide. TEM images also supports for the formation of uniform tin oxide and encapsulation of polypyrrole. SEAD pattern of the material reveals the uniform distribution of the tin oxide particle. The cloudy ring SAED pattern endorses for the polypyrrole matrix in the composite. The present study is an attempt to overcome the present-day volume expansion problem induced by the lithiation and de-lithiation in to the SnO2 particle. During this alloying reaction the particle undergoes large volume change. The polypyrrole is believe to be act as a back bone, which encapsulating tin particle and attached to the similar structure to form a sheet of the composite matrix. Since the polypyrrole is well known for its conductivity and the lithium transfer would be made ease. These said properties of the composite material is suitable for the superior capacity and its retention. Figure 1

TiO2 Nanotubes/Ionic Liquid Electrolyte System Enhances Li-Ion Battery Performance

High capacity advanced lithium ion batteries (LIBs) utilizes non-volatile ionic liquid (IL) electrolyte is considered a promising candidate to address the safety and durability issues of traditional LIBs. Compared to organic-based electrolyte, however, IL has lower ionic conductivity at almost temperature range and shows less effective contact with the electrodes in absence of organic solvent, thus created barrier of lithium transfer at the electrolyte-electrode interface, which in turn reduce the cell performance 1 . Current study is focused on the design of composite ionic liquid electrolyte which gives higher ionic conductivity coupled with the improved of interface stability. Highly conductive electrolyte could be achieved through optimizing synergistic function between ionic liquids, salt, and the PVdF substrate. By suitable composition of lithium-bis-(trifluoromethyl sulfonyl)imide (Li-TFSI) and 1-butyl-3-methyl imidazolium bis-(trifluoromethyl sulfonyl)imide (BMI-TFSI) ionic liquids in poly-(vyniliden fluoride-hexafluoropropylene) (PVDF-HFP) co-polymeric host material, optimized membrane morphology is achieved through phase inversion technique during membrane casting, where an unique pore structure is formed. High ionic conductivity in the order of 10-3 Scm-2 is observed in PVDF-HFP: BMI-TFSI: Li-TFSI (10:10:2, w/w) electrolyte system, which is found to be higher than that of commercial membrane with liquid electrolyte. . Furthermore, the addition of small amount of TiO2 nanotubes (TiNT) incorporated onto the ionic liquid electrolyte system further raises the ionic conductivity up to ~1.5 x 10-3 Scm-2 (25 oC) and ~8.0 x 10-3 Scm-2 (80 oC), which is attributed both to higher lithium salt dissociation in presence of TiO2 and the establishment of more direct ion conducting pathway 2 . Further addition of TiNT, however, leads to reduction of ionic conductivity, which drops significantly after 5 wt% (relative to the solvent) of TiNT addition, which is probably the result of inorganic self-aggregation. Wider thermal decomposition around ~400 oC from TGA and DSC shows a remarkable improvement in thermal stability of membrane containing TiNT. Battery performance in a Li/electrolyte-TiNT/LiFePO4 coin cells indicates relatively high discharge specific capacity around ~136 mAh/g at 0.05 C moderate electrochemical cycling and shows better cycling performance with almost constant ~ 99% coulombic efficiency as a result of improved electrolyte interface stability to the electrode.

Nanoscale Imaging of Lithium Ion Distribution During In Situ Operation of Battery Electrode and Electrolyte

A major challenge in the development of new battery materials is understanding their fundamental mechanisms of operation and degradation. Their microscopically inhomogeneous nature calls for characterization tools that provide operando and localized information from individual grains and particles. Here, we describe an approach that enables imaging the nanoscale distribution of ions during electrochemical charging of a battery in a transmission electron microscope liquid flow cell. We use valence energy-loss spectroscopy to track both solvated and intercalated ions, with electronic structure fingerprints of the solvated ions identified using an ab initio nonlinear response theory. Equipped with the new electrochemical cell holder, nanoscale spectroscopy and theory, we have been able to determine the lithiation state of a LiFePO4 electrode and surrounding aqueous electrolyte in real time with nanoscale resolution during electrochemical charge and discharge. We follow lithium transfer between electrode and electrolyte and image charging dynamics in the cathode. We observe competing delithiation mechanisms such as core-shell and anisotropic growth occurring in parallel for different particles under the same conditions. This technique represents a general approach for the operando nanoscale imaging of electrochemically active ions in the electrode and electrolyte in a wide range of electrical energy storage systems.

Interfacial phenomena between lithium ion conductors and cathodes

Nanocomposites of a lithium ion conductor Li 1.3 Al 0.3 Ti 1.7 (PO 4 ) 3 and electrode materials (TiO 2 and FePO 4 ) were prepared to investigate interfacial structure and ionic conductivity at the interface between the solid electrolyte and electrode materials. It was revealed that lithium ions in the solid electrolyte were attracted to the cathode materials with increasing electrode potential, which increases lithium vacancies in the solid electrolyte. For the FePO 4 containing composites, due to the high electrode potential, lithium transfer across the interface and ionic conduction through the cathode materials was remarkable. The results suggest that severe lithium depletion occurs and interfacial resistance is large at the interface of high ionic conductors and cathode materials. The space charge layer thickness is also discussed. • Nanocomposites of lithium ion conductors and electrode materials were fabricated. • Conductivity enhancement depended on charge carriers and cathode potentials. • High potential cathodes cause lithium depletion in high ionic conductors. • All the results were well explained with the space charge layer model.

The electrochemical performance of pitch coke anodes containing hollow carbon nanostructures and nickel nanoparticles for high-power lithium ion batteries

Pitch cokes with abundant hollow carbon nanostructures (HCNs) and nickel nanoparticles were prepared from pitch containing nickel nanoparticles by simple heat-treatment process. The effects of nickel content and heat-treatment temperatures on the electrochemical properties were analyzed systematically. Two kinds of pitch cokes were studied in detail and both of them revealed excellent electrochemical performances, such as high reversible capacity, excellent rate capability and good cycling properties that the capacity becoming bigger with cycling. The microstructure of the samples was characterized by X-ray diffraction and transmission electron microscopy. Combined with the electrochemical performances, it was assumed that the HCNs should play an important role in the enhancing electrochemical properties as the reservoir for the lithium storage and transfer. A sample composed mainly of HCNs was fabricated to verify the hypothesis.

Lithium Depletion in the Solid Electrolyte Adjacent to Cathode Materials

Nanocomposites of lithium ion conductors (Li2SiO3 and Li1.3Al0.3Ti1.7(PO4)3) and electrode materials (TiO2, Li0.01TiO2 and FePO4) were prepared to investigate interfacial structure and ionic conductivity at the interface between solid electrolytes and electrode materials. It was revealed that lithium ions in the solid electrolytes were attracted to the cathode materials with increasing electrode potential, which increases lithium vacancies in solid electrolytes. For the FePO4 containing composites, due to the high electrode potential, lithium transfer across the interface and ionic conduction through the cathode materials was remarkable. The results suggest that severe lithium depletion occurs and interfacial resistance is large at the interface of high ionic conductors and cathode materials.

Non-equilibrium Structural Evolution of the Lithium-Rich Li1+yMn2O4 Cathode within a Battery

Lithium-ion batteries are undergoing rapid development to meet the energy demands of the transportation and renewable energy-generation sectors. The capacity of a lithium-ion battery is dependent on the amount of lithium that can be reversibly incorporated into the cathode. This work directly quantifies the time- and current-dependent lithium transfer within a cathode functioning under conventional charge–discharge cycling. We examine Li1+yMn2O4 under real working conditions using in situ neutron powder diffraction and link the atomic-scale structure to the battery performance. The lithium location and content, oxygen positional parameter, and lattice parameter of the cathode are measured and linked to the battery’s charge/discharge characteristics. Lithium insertion (discharge) differs from extraction (charge), a feature that may explain the relative ease of discharge (compared with charge) of this material. An atomic-scale understanding of cathode functionality, such as revealed here, will direct improvements in battery performance at both the practical and the fundamental level.

Lithium recovery by electrochemical transfer junction based on intercalation host matrix

Electrochemical transfer junctions (ETJs) were synthesized via a chemical covering method onto a porous ceramic substrate (mullite/alumina). This layer of 100μm is composed of lithium metal oxides. The ETJ composites placed between two tanks lead to a lithium transfer by intercalation reactions by applying a current density between electrodes placed in both tanks. After proving the transfer efficiency, we combined this transfer with another one relative to cobalt ions with a Chevrel phase matrix in order to propose a one step process to recover simultaneously but separately both Li and Co cations.

Equilibrium studies on lithium(I) transfer into ionic liquid with a water-soluble octabromoporphyrin (H2(OBTMPyP)4+) from aqueous phase

A water-soluble octabromoporphyrin 2,3,7,8,12,13,17,18-octabromo-5,10,15,20-tetrakis(1-methylpyridinium-4-yl)porphyrin (H2(OBTMPyP)4+), H2P4+) and its lithium complex, Li(OBTMPyP)3+ , (LiP3+) , transferred quantitatively to an ionic liquid (IL), 1-butyl-3-methylimidazolium hexafluorophosphate (BMIM+PF6-) with no addition of other counter ions. The acid-dissociation constants of H2(OBTMPyP)4+ between aqueous and BMIM+PF6- phases were determined spectrophotometrically and found to be 10-7.67 and 10-11.33 at I = 0.1 for K a1,IL = [H+]aq[HP3+]IL/[H2P4+]IL and K a2,IL = [H+]aq[P2+]IL/[HP3+]IL , respectively. Since the acid-dissociation constants involve the partition of H2(OBTMPyP)4+ between aqueous and IL phases, the determined values are ten times as low as those observed in aqueous solution. The transfer equilibrium constants of LiP3+ and NaP3+ to IL defined by K MP,IL = [MP3+]IL/[M+]aq[P2+]IL (M = Li+ or Na+) were found to be 104.83 and 101.31 for K LiP,IL and KNaP,IL , respectively. LiP3+ transferred selectively in the presence of Na+ (K LiP,IL /K NaP,IL = 103.52) to IL phase through an ion-exchange mechanism between BMIM+PF6- and Li(OBTMPyP)3+ .

Lithium: Updated Human Knowledge Using an Evidence-Based Approach

Lithium use in mental diseases has changed over the years but remains a cornerstone of treatment in bipolar disorders. In two companion papers, we have reviewed existing (and especially recent) data on lithium efficacy and updated basic knowledge regarding the practical fundamentals of lithium therapy. The present paper reviews safety data on lithium available to date. Gastrointestinal pain or discomfort, diarrhoea, tremor, polyuria, nocturnal urination, weight gain, oedema, flattening of affect and exacerbation of psoriasis are typical complaints of patients receiving long-term lithium therapy. Renal involvement results in a reduced urinary concentrating capacity, expressed as obligate polyuria, with secondary thirst. With long-term therapy, this may result in nephrogenic diabetes insipidus. In addition, glomerular filtration rate falls slightly in about 20% of patients. The view that only a few patients receiving long-term lithium are at increased risk of glomerular impairment and progressive renal insufficiency should be regarded with caution. The risk is increased in case of concomitant diseases or medications. Lithium treatment may inhibit thyroid hormone release and induce goitre. Consequently, the prevalence of both overt and subclinical hypothyroidism is increased, with circulating thyroid auto-antibodies frequently being found. Much less commonly, thyrotoxicosis may also develop in association with lithium therapy. Long-term lithium treatment may also be associated with persistent hyperparathyroidism and hypercalcaemia, as well as with hypermagnesaemia. Overweight of up to 4-10 kg is found in approximately 30% of lithium-treated patients. Most neurological manifestations are benign, for example, the fine postural and/or action tremor present in 4-20% of patients. This is increased by high caffeine consumption and concomitant use of other psychotropic agents. A number of rare, potentially serious neurological adverse effects have been reported, including extrapyramidal symptoms, 'pseudotumour cerebri' or occasionally cerebellar symptoms. Severe neurological sequelae are exceptional. Cognitive disturbances are often mentioned as a lithium-related adverse effect. The few controlled studies do show a statistically significant negative effect of lithium on memory, vigilance, reaction time and tracking. There are frequent reports of mild effects of lithium on cognition at therapeutic serum concentrations. A number of deaths associated with lithium treatment have been reported. The most serious issue is that of non-accidental overdose, i.e. either long-term overdosage or acute overdose on long-term treatment. Progressive renal insufficiency, an exceptional complication of long-term lithium therapy, may also have a fatal outcome. In relation to pregnancy, lithium salts are rated as category D (positive evidence of risk). Therefore, prescription of lithium should be avoided during the first trimester of pregnancy unless the benefit to the mother exceeds the risk to the fetus. Although lithium transfer into breast milk is well established, the long-term fate of babies breast-fed by mothers receiving lithium therapy is unknown. Whether lithium therapy is safe in breast-feeding women is controversial. Although there is no absolute contraindication, it is known that the kidney is particularly sensitive to lithium just after birth. Intoxication in patients on long-term treatment with lithium in the absence of history of acute ingestion is not rare. Contributing factors include change in daily dose, long-term high dosage, kidney disease or drug interaction. In suspected cases, serum concentrations should be obtained early and repeatedly. In addition to supportive measures, haemodialysis is the treatment of choice for severe cases. Thorough knowledge of the limitations and drawbacks of lithium therapy is mandatory for its optimal use, especially at a time when its risk/benefit profile needs to be compared accurately with that of antiepileptic drugs and other mood stabilizing medications.