This is a major issue for electric vehicle batteries, which often spend much of their day sitting out in bright sunlight. Strangely enough, batteries are under the most strain when they're fully charged or completely empty.
The real sweet spot for a battery is 50 per cent charge as that means that half of its moveable lithium ions are in the lithium cobalt oxide layer and the other half are in the graphite layer. This equilibrium puts the least amount of strain on the battery, and extends the number of charge cycles it can withstand before degrading.
So really, if you were super-keen on keeping your battery living as long as possible, you should keep its charge between 20 and 80 per cent. This means that it spends as little time as possible with lots of lithium ions crammed into either layer, a situation which causes the layers to expand, putting physical strain on them. Maybe not, then. This one is closely linked to the above myth. A smartphone battery typically remains working at optimal capacity for about two to three years.
You can replace it yourself, DIY-style, but manufacturers are making this increasingly difficult to do. Instead, it might be easier paying someone else for the service. Read more: These are the best smartphones for any budget in There are numerous different varieties of battery which serve many different purposes, but two we hear about more than any are lithium and lithium-ion batteries.
You might have had to make a decision in the past regarding these two different battery types, but do you really know what they are? To understand the similarities and differences between Lithium and Lithium-ion batteries, you need a basic understanding of what constitutes a battery, and how they work.
When the cathode and anode of a battery are connected to an electrical circuit, a chemical reaction occurs between the anode and electrolyte. Electrons flow through the circuit from the anode, and then enter back through the cathode and prompt another chemical reaction.
These reactions continue until the materials are consumed, at which point no more electricity is produced by the battery. Both Lithium and Lithium-ion batteries produce portable electricity in this manner and can be used to power all sorts of different devices and electrical circuits.
Batteries are incredibly useful components that allow us all sorts of luxuries, without them we would have to start cars by hand, and phones would still all be attached to the wall. Lithium batteries are primary cell batteries, which means they cannot be recharged once empty. They use the metal lithium as an anode.
Lithium batteries have a high charge density, meaning they last longer than other batteries and can hold more power. Depending on their design, lithium batteries can produce electricity with a voltage of between 1. The metal used in lithium batteries is very reactive, pure lithium will instantly react with water, and even moisture in the air. Lithium batteries are used in many electronic devices, from electric toy cars to full-sized vehicles.
Although their high power capacity makes them very useful, the fact that they cannot be easily or even safely recharged meant that many companies began to look for other alternatives.
The disposable batteries many of us have around our homes are not very good for the environment, which is why many people and companies decide to use Lithium-ion batteries like this beautiful W Lithium Polymer Battery instead. A lithium battery should never be recharged while lithium-ion batteries are designed to be recharged hundreds of times. They have a higher energy density than most other types of rechargeables. This means that for their size or weight they can store more energy than other rechargeable batteries.
They also operate at higher voltages than other rechargeables, typically about 3. Lithium-ion batteries also have a lower self discharge rate than other types of rechargeable batteries. This means that once they are charged they will retain their charge for a longer time than other types of rechargeable batteries.
Lithium-ion batteries will retain most of their charge even after months of storage. So in summary; lithium-ion batteries can be smaller or lighter, have a higher voltage and hold a charge much longer than other types of batteries. This is because they are much more complex to manufacture. Li-ion batteries actually include special circuitry to protect the battery from damage due to overcharging or undercharging.
They are also more expensive because they are manufactured in much smaller numbers than NiMH or NiCd batteries. Li-ion batteries are becoming less expensive and over time we should see their price decrease significantly. How long have they been on the market? Are they reliable? Are they safe? Lithium ion is considered a "volatile" cell chemistry so I am a bit skeptical but finally a manufacturer has gone and ventured into that territory.
This could be both disruptive and awesome. More to come. Lithium-ion batteries also require sophisticated chargers that can carefully monitor the charge process. The higher the voltage the more ions can be inserted. The page linked here contains our research and some quantitative data on the relative capacity of lithium-ion batteries that are charged below 4. An advantage to charging at lower voltages is that the cycle life goes up dramatically.
This link shows how lithium iron phosphate batteries' capacity changes with charge voltage. Charge voltage experiments with lithium iron phosphate batteries showing how capacity varies with charge voltage. Charging Lithium ion batteries at slow rates When the charge rate during the constant current phase is low, the charger process will spend less time during the constant voltage tail.
If you charge below about 0. This can be used as an alternative charge algorithm. Just charge below 0. Safety Every lithium ion battery pack should have a method of keeping the cell balanced and preventing them from being over-discharged.
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