There's been a lot in the press lately about lithium-ion batteries. Conference panelists, energy researchers, car manufacturers and, of course, environmentalists are discussing the possibility of running vehicles entirely on battery power.
Most of us are more familiar with lithium-ion batteries in consumer electronics - laptops, MP3 players, cell phones, digital cameras, rechargeable battery kits...But, uh, what exactly are they again? Straight lithium batteries are little packets of extractable power which use lithium in its pure metallic form. Straight lithium batteries are considered a "primary battery," or a battery that cannot be recharged. Secondary batteries or cells can be recharged.
Lithium-ion batteries, on the other hand, are a fairly new development in which more stable lithium compounds are used. One of the primary advantages of lithium-ions, or Li-ions, is that they can be recharged hundreds, sometimes even thousands of times. Two or more secondary cells are restored to full charge through electrical energy in this process.
But perhaps we should backtrack. Why are some batteries rechargeable and others not? It's actually fairly simple. Rechargeable batteries can recoup their precious energy because they contain electrochemical cells in which the electrochemical reaction that releases energy is reversible. These cells are a type of accumulator. In the case of Li-ions, the ions move between two parts - the anode and the cathode. Anode to cathode movement charges; cathode to anode movement recharges. Other types of secondary cells include lead and sulfuric acid combos, nickel cadmium (NiCD), lithium-ion polymer and nickel metal hydride (NiMH), the last of which is used in most hybrid electric vehicle (HEV) batteries.
The advantages of lithium-ions over non-rechargeable and other rechargeable batteries are numerous. For one, Li-ions have a higher energy density than their counterparts, meaning they store much more energy for their size and weight than other rechargeables. More energy means fewer cells are needed to accomplish the same task. More cells in the same space as, for instance, NiMHs means more energy. They also operate at higher voltages - three times that of NiMH batteries - and have a lower self-discharge rate, so they lose energy slowly while not in use.
The implications for the auto industry are profound. What if cars really could run without gasoline? Could this go so far as to affect the world economy? How powerful are these things, really?
A prominent energy researcher for a government agency believes Li-ion batteries will soon replace NiMH models in HEVs. Major auto manufacturers are already planning to release full plug-ins (cars that run on electrical energy often stored in Li-ion batteries) by 2010.
While these little powerhouses can come at a premium of up to $10,000 by some estimations, many experts believe that number will dramatically decrease as the law of supply and demand takes effect.
Lest the battery world becomes unrealistically rosy however, Li-ions do have disadvantages. One, they're dramatically more expensive. Two, Li-ions require more sophisticated chargers - again, creating the problem of increased cost and low supply. Three, Li-ions are sensitive to the environmental conditions. Temperatures that are too hot or too cold can reduce their functionality and life. Four, Li-ion batteries slowly but predictably degrade over time reducing their capacity.
Certain manufacturers for the auto industry are foreseeing the coming of this technology and beginning to produce hybrid vehicle battery pack systems designed for single or multi-element battery cells that can be globally integrated with any lithium-ion or NiMH battery. The best of them have reusable building block technologies, can accommodate a range of voltages, have systems that maintain the health of the battery cells and are applicable to mild hybrids, full hybrids, or electric vehicles. These "packs" are an important part of what could make quicker mass integration into the hybrid market possible.
Times they are a changin'. Who wouldn't want a fuel-free car? Regardless of certain disadvantages, Li-ion innovations - and accommodations to suit them - are coming. They're just too promising.
Most of us are more familiar with lithium-ion batteries in consumer electronics - laptops, MP3 players, cell phones, digital cameras, rechargeable battery kits...But, uh, what exactly are they again? Straight lithium batteries are little packets of extractable power which use lithium in its pure metallic form. Straight lithium batteries are considered a "primary battery," or a battery that cannot be recharged. Secondary batteries or cells can be recharged.
Lithium-ion batteries, on the other hand, are a fairly new development in which more stable lithium compounds are used. One of the primary advantages of lithium-ions, or Li-ions, is that they can be recharged hundreds, sometimes even thousands of times. Two or more secondary cells are restored to full charge through electrical energy in this process.
But perhaps we should backtrack. Why are some batteries rechargeable and others not? It's actually fairly simple. Rechargeable batteries can recoup their precious energy because they contain electrochemical cells in which the electrochemical reaction that releases energy is reversible. These cells are a type of accumulator. In the case of Li-ions, the ions move between two parts - the anode and the cathode. Anode to cathode movement charges; cathode to anode movement recharges. Other types of secondary cells include lead and sulfuric acid combos, nickel cadmium (NiCD), lithium-ion polymer and nickel metal hydride (NiMH), the last of which is used in most hybrid electric vehicle (HEV) batteries.
The advantages of lithium-ions over non-rechargeable and other rechargeable batteries are numerous. For one, Li-ions have a higher energy density than their counterparts, meaning they store much more energy for their size and weight than other rechargeables. More energy means fewer cells are needed to accomplish the same task. More cells in the same space as, for instance, NiMHs means more energy. They also operate at higher voltages - three times that of NiMH batteries - and have a lower self-discharge rate, so they lose energy slowly while not in use.
The implications for the auto industry are profound. What if cars really could run without gasoline? Could this go so far as to affect the world economy? How powerful are these things, really?
A prominent energy researcher for a government agency believes Li-ion batteries will soon replace NiMH models in HEVs. Major auto manufacturers are already planning to release full plug-ins (cars that run on electrical energy often stored in Li-ion batteries) by 2010.
While these little powerhouses can come at a premium of up to $10,000 by some estimations, many experts believe that number will dramatically decrease as the law of supply and demand takes effect.
Lest the battery world becomes unrealistically rosy however, Li-ions do have disadvantages. One, they're dramatically more expensive. Two, Li-ions require more sophisticated chargers - again, creating the problem of increased cost and low supply. Three, Li-ions are sensitive to the environmental conditions. Temperatures that are too hot or too cold can reduce their functionality and life. Four, Li-ion batteries slowly but predictably degrade over time reducing their capacity.
Certain manufacturers for the auto industry are foreseeing the coming of this technology and beginning to produce hybrid vehicle battery pack systems designed for single or multi-element battery cells that can be globally integrated with any lithium-ion or NiMH battery. The best of them have reusable building block technologies, can accommodate a range of voltages, have systems that maintain the health of the battery cells and are applicable to mild hybrids, full hybrids, or electric vehicles. These "packs" are an important part of what could make quicker mass integration into the hybrid market possible.
Times they are a changin'. Who wouldn't want a fuel-free car? Regardless of certain disadvantages, Li-ion innovations - and accommodations to suit them - are coming. They're just too promising.
