{"id":8550,"date":"2022-02-13T08:59:34","date_gmt":"2022-02-13T13:59:34","guid":{"rendered":"https:\/\/dronebotworkshop.com\/?p=8550"},"modified":"2023-04-12T06:09:54","modified_gmt":"2023-04-12T10:09:54","slug":"lipo-safety","status":"publish","type":"post","link":"https:\/\/dronebotworkshop.com\/lipo-safety\/","title":{"rendered":"Safely using LiPo Batteries"},"content":{"rendered":"\n

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Today, we will be taking a detailed look at the safe use of LiPo batteries. Used properly, these incredible sources of energy can power up your radio-controlled or robotic projects, no matter how large or current-consuming.<\/span><\/p>\n

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However, improper use of LiPo batteries can severely shorten their lifespan, or worse, result in a deadly LiPo fire. And we certainly want to avoid that at all costs!<\/span><\/p>\n

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Let\u2019s see how to safely use LiPo Batteries.<\/span><\/p>\n

Introduction<\/span><\/h2>\n

LiPo, or Lithium-Ion Polymer Batteries, are one of the great technical advances to come around in the last 20 years. These powerful energy sources are used in mobile devices, radio-controlled aircraft and vehicles, electric vehicles, and, of course, robotics.<\/span><\/p>\n

LiPo batteries have a very high \u201cspecific energy, or mass-to-energy ratio. In simple terms, they pack more power for their weight than any other type of battery, including other Lithium-based power cells.\u00a0\u00a0<\/span><\/p>\n

In terms of cost, LiPo batteries may seem expensive, but when you factor in the amount of power they provide and the weight they save they are pretty cost-effect.<\/span><\/p>\n

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However, LiPo batteries require more tender loving care than regular batteries. They have very stringent requirements for charging, discharging, storage, and disposal, and not observing these requirements can result in poor performance, reduced battery lifespan, or even a fire or explosion.<\/span><\/p>\n

But, when used properly, LiPo batteries can be perfectly safe and can allow you to build projects that you couldn\u2019t power up otherwise.<\/span><\/p>\n

Let\u2019s learn more about LiPo batteries.<\/span><\/p>\n

LiPo Batteries<\/span><\/h2>\n

You\u2019ve probably seen a number of batteries that use \u201cLithium\u201d technology. So how do LiPo batteries fit in? Learning a bit about how they were developed can help answer that question.<\/span><\/p>\n

LiPo History<\/span><\/h3>\n

All rechargeable Lithium cells or batteries (a \u201cbattery\u201d is a collection of cells) are based upon the principle of the reversible storage of ions, a technique pioneered in the late 1970s.<\/span><\/p>\n

In 1980 the very first lithium cell was developed at Oxford University.\u00a0 These were Lithium-Ion cells, and they used a liquid electrolyte to hold the lithium ions.<\/span><\/p>\n

The first commercial lithium-ion, or Li-ion, battery was produced by Sony in 1991, for use in some of their camcorders.<\/span><\/p>\n

In a LiPo battery, the liquid electrolyte is replaced with a gel polymer. The first LiPo battery was released by Ericsson in 1999, for use in their mobile phones.<\/span><\/p>\n

One very popular use these days for LiPo batteries is in radio-controlled aircraft, quadcopters, and ground vehicles. Their incredible power to mass ratio allows for a long operating time while minimizing weight, which is especially important in aircraft.<\/span><\/p>\n

How LiPo Batteries Work<\/span><\/h3>\n

A LiPo battery, or more accurately a cell in a LiPo battery, is made up of a container that holds a polymer gel electrolyte. Each end of the container has a current collector, one end is the anode and the other the cathode. There is a separator in the middle of the cell, dividing it into two sections.<\/span><\/p>\n

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Lithium ions are deposited in one of the sections of the cell.\u00a0 As to which section, that depends on if the cell is charging or discharging.<\/span><\/p>\n

If the cell is discharging, supplying power to a connected load, then the Lithium ions are released from the anode side and travel to the cathode side.\u00a0 Electrons travel through the load from the cathode to the anode.<\/span><\/p>\n

If the cell is being charged, then the movement of the Lithium ions is in the opposite direction, from the cathode to the anode.<\/span><\/p>\n

Understanding LiPo Specifications<\/span><\/h3>\n

In order to select the proper LiPo battery for your application, you\u2019ll need to know how to read and interpret its specifications.\u00a0 If you have used other batteries, then some terminology will be familiar, while some other terms may be confusing.<\/span><\/p>\n

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Let\u2019s end that confusion, shall we?<\/span><\/p>\n

Voltage and Cell Count<\/span><\/h4>\n

A LiPo battery, like any battery, consists of one or more cells wired in series. It is also possible to have cells in parallel, as we will see in a bit.<\/span><\/p>\n

The total output voltage of a LiPo battery is therefore dependent upon the number of cells wired in series. However, that voltage is not constant.<\/span><\/p>\n

The voltage specified on a LiPo battery is the total value of the Nominal voltage of each cell. <\/span>Nominal voltage is the average voltage of the cell and is defined as 3.7-volts per cell<\/b>. So a two-cell LiPo battery will have a nominal voltage of 7.4-volts, a 3-cell battery will be 11.1-volts.<\/span><\/p>\n

The fully-charged voltage on a LiPo cell is 4.2-volts<\/b>, so the two-cell battery will have a total output of 8.4-volts and the 3-cell LiPo battery will read 12.6-volts when fully charged.<\/span><\/p>\n

The minimum safe voltage per cell is 3-volts<\/b>. Most users never let their LiPo batteries get down to that level.<\/span><\/p>\n

The number of cells in series within a LiPo battery is defined by its \u201cS\u201d number<\/b>:<\/span><\/p>\n