There are a lot of batteries as you learned with the article about the battery CR2032. You should also know by now that there are modules for Arduino like the TP4056 which is specific for charging batteries. Now, in this new article you will learn more about LiPo batteries. That is, a specific type of lithium battery that is gaining a lot of fame in the market together with the Li-Ion.
I also recommend you to take a look at the article about the battery charger IMAX B6, in which I wrote a section about the most important types of batteries, accumulators and batteries with their differences, advantages and disadvantages. That might help you to understand what is going to be discussed here about LiPo batteries.
The lithium (Li) is an element of the periodic table corresponding to a whitish alkaline metal. It is highly flammable, ductile and very light (more than aluminium). It corrodes rapidly on contact with oxygen in the air, and does not exist in a free state in nature. For that reason, it must be processed after the option in the mines.
It’s not a rare metal, since 65 parts per 1,000,000 of the Earth’s crust are lithium. But nowadays it has become very precious, as is the case with coltan ore, due to its applications in the technology industry, mainly to manufacture batteries with it.
Lithium cannot be immersed in water either, as when it is mixed with water it can react and burn, as with Na. Therefore, when it comes into contact with the skin it can cause injuries, since sweat or skin humidity can generate this combustion. All the more reason for battery manufacturers to make sure that batteries are well protected to avoid possible accidents.
As I said, one of the main applications of lithium is batteries. Both for many electric cars such as F1, as well as for the electronics sector (mobile phones, tablets, laptops, …). It is true that it has not been used before, as it was another type of battery that was imposed on the market.
But the discovery of the properties of lithium, such as its rapid charging, the negligible problems of the dreaded memory and lifetime effect, its energy density (smaller and more powerful batteries), etc., has made it soon to be the dominant type of battery.
Within the lithium batteries there are several families that stand out from the rest, although lately they are experimenting with other more exotic aspects. These types are:
- Cobalt-Lithium Oxide: These have a high energy density and are very durable, but can present safety problems.
- Lithium-Magnesium oxide: they are very safe, but their performance and efficiency are not always good, especially at high temperatures.
- Lithium-iron phosphate: is another of the best in terms of safety and long durability, supporting more than 2000 cycles of loading and unloading.
- Li-Ion: they are rechargeable lithium batteries and have a cylindrical or tubular architecture. They have a good density, durability and safety.
- LiPo: LiPo batteries are the ones we are interested in for this article, and they are flat. They are also rechargeable and have similar characteristics to Li-Ion.
The ones you’ve heard the most about, because they’re the best, are the Li-Ion and the LiPo. Which have some notable differences…
LiPo vs. Li-Ion batteries
As I said, LiPo and Li-Ion batteries are similar in many ways. Not only do they use lithium as their base element, they also have a fairly long life. They last at least about 1000 charge/discharge cycles, although it’s usually 500 cycles without any noticeable change in performance.
On the other hand, both have good densities, so you can create powerful and high capacity batteries with a reduced weight and size. That’s why they have been imposed on mobile devices.
And finally, they both share an evil. And that’s their safety, because they have a combustion hazard, as we’ve seen in some poorly designed mobiles. To avoid problems, they should not be exposed to high temperatures either.
As far as the differences between LiPo and Li-Ion:
- Li-Ion: they use a lithium salt electrolyte contained in an organic solvent (liquid), which will provide the necessary ions to circulate current between the cathode and the anode during the discharge. This is how a potential difference is generated to make the connected devices work. By the way, as far as the charge is concerned, the process is reversed and the ions are moved from the anode to the cathode.
- LiPo: The lithium salt is contained in a gel (usually a polymer), which makes the possibility of spillage less. They are usually somewhat more flexible, so they are interesting for models that are deformed. The problem is that they are more flammable than Li-Ion.
A user level, you won’t find any difference. You will see similar performance, capabilities and physical characteristics.
Tips for caring for lithium batteries
LiPo batteries, like Li-Ion batteries, last quite a while as I mentioned, but that doesn’t mean you shouldn’t take care of them. To make them last longer, you can follow these very simple tips:
- Always charge the battery when needed. It should be removed from the device that contains it if possible or at least turn off the device that is using it.
- Discharging the battery to its limit is not the best option in these cases.
- You don’t have to wait until it is 100% to remove the charger and use it if you need to. The memory effect here is slight.
- Do not subject the battery to high temperatures, as this will dramatically deteriorate it.
- You should not use the chargers for quick charging. This technology is fast and practical, but by subjecting them to greater stress due to the intensity of the charge, their useful life is reduced.
- If you are going to store the battery for long periods of time without using it (several months), then you should make sure that it is charged to at least 40% or more.
It is possible that a lithium chloride film may form on the positive pole of the battery when it is not used. Although this makes it difficult for the electrons to circulate, it is not too serious, and is eliminated with use.
Buy LiPo batteries for your projects
If you are thinking of acquiring a LiPo battery to power your projects, you should know that you can find them in several formats and with different technical characteristics. Besides the voltage and intensity it can provide, the most important data is its capacity.
The capacity of these batteries is measured in mAh, i.e. the amount of mA per hour they can supply. For example, a 1000 mAh battery could supply 1000mA for one hour. But it could also, for example, supply 2A for half an hour, or be running for 4 hours supplying 0.5A. On these values the duration will depend…
You should analyze the energy needs of your projects to determine what capacity you need. Here are some examples of products you can buy on Amazon:
Remember that the voltage is not the most important thing, since you could make use of regulators to be able to adapt it to what you need…