The active components in a secondary cell are the chemicals that make up the positive and negative active materials, and the electrolyte. The positive and negative are made up of different materials, with the positive exhibiting a reduction potential and the negative having an oxidation potential. The sum of these potentials is the standard cell potential or voltage.
In primary cells the positive and negative electrodes are known as the cathode and anode, respectively. Although this convention is sometimes carried through to rechargeable systems—especially with lithium-ion cells, because of their origins in primary lithium cells—this practice can lead to confusion. In rechargeable cells the positive electrode is the cathode on discharge and the anode on charge, and vice versa for the negative electrode.
Types Edit
See also: List of battery types
Type Voltagea Energy densityb Powerc E/$e Self-disch.f Cyclesg Lifeh
(V) (MJ/kg) (Wh/kg) (Wh/L) (W/kg) (Wh/$) (%/month) (#) (years)
Lead–acid 2.1 0.11-0.14 30-40 60-75 180 5-8 3-4% 500-800 5-8 (automotive battery), 20 (stationary)
Alkaline 1.5 0.31 85 250 50 7.7 <0.3 100-1000 <5
Nickel–iron 1.2 0.07–0.09[7] 19–25[7] 100 5-7.3[8] 20-40% 50+
Nickel–cadmium 1.2 0.14-0.22 40-60 50-150 150 1.25-2.5[8] 20% 1500
Nickel–hydrogen 1.5 0.27 75 60 220 20,000+ 15+ (satellite application with frequent charge-discharge cycles)
Nickel–metal hydride 1.2 0.11-0.29 30-80 140-300 250-1000 2.75 30% 500-1000
Nickel–zinc 1.7 0.22 60 170 900 2-3.3 100-500
Lithium Cobalt Oxide 3.6 0.58 150-250 250-360 1800 2.8-5[9] 5-10% 400–1200[10] 2-6
Lithium-ion polymer 3.7 0.47-0.72 130-200 300 3000+ 2.8-5.0 5% 500~1000 2-3
Lithium iron phosphate 3.25 0.32-0.4 80-120 170‡ 1400 3.0-24[11] 8.000 100% DOD to 74% capacity[12] >10
Lithium sulfur[13] 2.0 0.94-1.44[14] 400[15] 350 ~1400[16]
Lithium–titanate 2.3 0.32 90 4000+ 0.5-1.0‡ 9000+ 20+
Sodium-ion[17] 1.7 30 3.3 5000+ Testing
Thin film lithium ? 300[18] 959[18] 6000[18] ?p[18] 40000[18]
Zinc-bromide 0.27-0.31 75-85
Zinc-cerium 2.5[19] Under testing
Vanadium redox 1.15-1.55 0.09-0.13 25-35[20] 20%[21] 14,000[22] 10 (stationary)[21]
Sodium-sulfur 0.54 150
Molten salt 2.58 0.25-1.04 70-290[23] 160[8] 150-220 4.54[24] 3000+ <=20
Silver-oxide 1.86 0.47 130 240
Quantum Battery (oxide semiconductor)[25][26] 1.5-3 500 8000(W/L) 100,000
‡ citations are needed for these parameters
Notes
a Nominal cell voltage in V.
Graph of mass and volume energy densities of several secondary cells
b Energy density = energy/weight or energy/size, given in three different units
c Specific power = power/weight in W/kg
e Energy/consumer price in W·h/US$ (approximately)
f Self-discharge rate in %/month
g Cycle durability in number of cycles
h Time durability in years
i VRLA or recombinant includes gel batteries and absorbed glass mats
p Pilot production
Common types
The lead–acid battery, invented in 1859 by French physicist Gaston Planté, is the oldest type of rechargeable battery. Despite having a very low energy-to-weight ratio and a low energy-to-volume ratio, its ability to supply high surge currents means that the cells have a relatively large power-to-weight ratio. These features, along with the low cost, makes it attractive for use in motor vehicles to provide the high current required by automobile starter motors.
The nickel–cadmium battery (NiCd) was invented by Waldemar Jungner of Sweden in 1899. It uses nickel oxide hydroxide and metallic cadmium as electrodes. Cadmium is a toxic element, and was banned for most uses by the European Union in 2004. Nickel–cadmium batteries have been almost completely superseded by nickel–metal hydride (NiMH) batteries.
The nickel–metal hydride battery (NiMH) became available in 1989.[27] These are now a common consumer and industrial type. The battery has a hydrogen-absorbing alloy for the negative electrode instead of cadmium.
The lithium-ion battery was introduced in the market in 1991, and in is the choice in most consumer electronics and have the best energy density and a very slow loss of charge when not in use.
Lithium-ion polymer batteries are light in weight, offer slightly higher energy density than Li-ion at slightly higher cost, and can be made in any shape. They are available[28] but have not displaced Li-ion in the market.
Experimental types Edit
The lithium sulfur battery was developed by Sion Power in 1994.[29] The company claims superior energy density to other lithium technologies.
The thin film battery (TFB) is a refinement of lithium ion technology by Excellatron.[31] The developers claim a large increase in recharge cycles to around 40,000 and higher charge and discharge rates, at least 5 C charge rate. Sustained 60 C discharge and 1000C peak discharge rate and a significant increase in specific energy, and energy density. Infinite Power Solutions makes TFB for microelectronic applications.
A smart battery has voltage monitoring circuit built inside. Carbon foam-based lead acid battery: Firefly Energy developed a carbon foam-based lead acid battery with a reported energy density of 30-40% more than their original 38 Wh/kg, with long life and very high power density.
UltraBattery, a hybrid lead-acid battery and ultracapacitor invented by Australia's national science organisation CSIRO, exhibits tens of thousands of partial state of charge cycles and has outperformed traditional lead-acid, lithium and NiMH-based cells when compared in testing in this mode against variability management power profiles. UltraBattery has kW and MW-scale installations in place in Australia, Japan and the U.S.A. It has also been subjected to extensive testing in hybrid electric vehicles and has been shown to last more than 100,000 vehicle miles in on-road commercial testing in a courier vehicle. The technology is claimed to have a lifetime of 7 to 10 times that of conventional lead-acid batteries in high rate partial state-of-charge use, with safety and environmental benefits claimed over competitors like lithium-ion. Its manufacturer suggests an almost 100% recycling rate is already in place for the product.
The potassium-ion battery delivers around a million cycles, due to the extraordinary electrochemical stability of potassium insertion/extraction materials such as Prussian blue.
The sodium-ion battery is meant for stationary storage and competes with lead–acid batteries. It aims at a low total cost of ownership per kWh of storage. This is achieved by a long and stable lifetime. The effective number of cycles is above 5000 and the battery is not damaged by deep discharge. The energy density is rather low, somewhat lower than lead–acid.
The quantum battery (oxide semiconductor) was developed by MJC. It is a small, lightweight cell with a multi-layer film structure and high energy and high power density. It is incombustible, has no electrolyte and generates a low amount of heat during charge. Its unique feature is its ability to capture electrons physically rather than chemically.[36]
In 2007, Yi Cui and colleagues at Stanford University's Department of Materials Science and Engineering discovered that using silicon nanowires as the anode of a lithium-ion battery increases the anode's volumetric charge density by up to a factor of 10, leading to the development of the nanowire battery.
Another development is the paper-thin flexible self-rechargeable battery combining a thin-film organic solar cell with an extremely thin and highly flexible lithium-polymer battery, which recharges itself when exposed to light.
Ceramatec, a research and development unit of CoorsTek, as of 2009 was testing a battery comprising a chunk of solid sodium metal mated to a sulfur compound by a paper-thin ceramic membrane which conducts ions back and forth to generate a current. The company claimed that it could fit about 40 kilowatt hours of energy into a package about the size of a refrigerator, and operate below 90 °C; and that their battery would allow about 3,650 discharge/recharge cycles (or roughly 1 per day for one decade).
Battery electrodes can be microscopically viewed while bathed in wet electrolytes, resembling conditions inside operating batteries.
In 2014, an Israeli company, StoreDot, claimed to be able to charge batteries in 30 seconds.