lithium polymer etiquette: a comprehensive guide to working with lipo

In this structure, I will review the basics of proper charging, discharge, processing, use, storage, and care of lithium polymer batteries, this way you can use them safely and effectively in future projects.
Now, this is by no means be-all and end-
All the information, for your particular device, it is always important to consult the instruction manual, but I think this instruction manual will provide a good knowledge base for the theme of these awesome batteries.
If you are new to lithium polymer/lithium polymer batteries, you need to know a lot of terms before we start.
Everything seemed a bit daunting at the beginning, but with some basic understanding, it was all very simple, so let\'s get started.
When you see the data sheet or shell of LiPo, you will notice that it has a lot of specs.
Cell arrangement-
Description in xSyP format (
Where x and y are integers)
, This tells you how the battery in the battery is wired.
The battery consists of the battery, the voltage of the battery is determined by the battery chemistry, and the capacity is determined by the energy density and physical size of the battery.
S represents series and P represents parallel connection.
As you may know, the series increases the voltage of the battery, and the parallel increases the capacity of the battery, so the battery combination in series and parallel causes the battery.
The battery shown in the second picture shows that it has a 3s1 p arrangement, which means that it has 3 batteries, they are all connected in series and not in parallel.
This may seem confusing because it says \"1 P\", but imagine this arrangement as a grid.
By multiplying 3 and 1, you can get the total number of batteries in the battery, in which case the total number of batteries is 3.
If it is a 3S2P battery, there will be 2 sets of 3 series-
The wired unit is connected in parallel and a total of 6 units are generated.
Parallel arrangement is often omitted when discussing batteries because most packages are 1 p (
So you might as well say 3 S instead of saying that you are using the 3s1 p package. Capacity -
Usually mAh (milliamp hours)
This is determined by the arrangement of cells (parallel)
And tell you how long the battery can last when charging (
Not so simple though).
As shown in the figure, the 2600 mAh displayed on the battery is equal to 2. 6Ah (amp hours)
, Formats that you may be more familiar with larger batteries, such as SLA (
Sealed lead acid)
There\'s one in your car, about 50 degrees.
When the capacity is 2600, the battery can be in 2.
6 amps an hour (
So \"amp Hours \"), 1.
2 hours, 3 amps, etc.
Before \"juice\" runs out.
\"Because the displayed batteries are arranged in 1 p, the capacity of each battery is 2600 mAh. Voltage -
The voltage of the battery is also determined by the battery arrangement (series)
There are several common voltage measurements to note: charging-
Full-voltage
The rechargeable LiPo battery is 4.
20 V, charging on it will damage the battery. Nominal -
This can be considered a \"half
The voltage to charge because it is 3.
70 v, between charge and discharge.
Nominalvoltage is the voltage used by the manufacturer when describing the battery voltage.
Discharged -
The voltage of the discharge LiPo battery is 3.
00 V, the discharge under this will definitely damage the battery.
Because the displayed battery has a 3 s arrangement, its nominal voltage is 11. 1V (3. 70V*3 cells).
The 3 s package fully charged is 12.
The 60 v and a fully discharged 3 s package are 9. 00V.
Constant C rating (Discharge)-
Constant C rating (
Related to emissions)
Tell you how many amps you can safely extract from the battery.
\"C\" in XC rating \"(
Where x is an integer)
Actually represents the capacity of the battery in Ah.
By multiplying the coefficient of the C rating by the capacity of the battery, you can determine the number of amps you can draw.
In the case of this battery, the capacity is 2600 mAh (2. 6Ah)
And C level of 55C (
Too high, FYI)
I can take 55*2.
6 and get the maximum constant output of my battery, that is 143A. Sudden C level (Discharge)-
In addition to a constant C rating, there is a higher burst C rating.
In most cases, the rating of \"burst\" is 10 seconds.
Although the picture is not marked on the battery itself, the file says that the 10-second burst rating of the battery is 80 ° c. So, 80*2. 6 is 208A explosion. That\'s a lot!
It is worth noting that your LiPo does not last for a long time when many amplifiers are extracted from it.
2600 mAh LiPo will last about 45 seconds at 208A. C Rating (Charge)-
Determined in the same way as the discharge C rating, the charge C rating tells you what current can safely charge the battery.
This information is usually listed on the back of the battery with all the security information.
For the battery shown, it happens to be 5C, which means it can be charged under 13A (2. 6*5).
We will discuss more about the charges later. . .
Now that we have some battery theory, let\'s take a look at some LiPo batteries.
All LiPo batteries (should)
There are two sets of wires coming out of them: discharge leads and balance leads (
Sometimes called balance tap).
Each information is positive with thicker wires (red, +, anode)and negative (black, -, cathode)
And is used to discharge LiPo according to their name.
Use a balance lead when charging the battery to ensure that all the batteries in the battery are charged evenly.
One side of the balance connector usually has a public ground connection and a positive connection to each battery in the battery.
Therefore, depending on the number of batteries of the battery, it will have a balance connector with a different number of pins.
In order to charge the LiPo battery, you have to use the LiPo-
Compatible charger.
If you want to charge a lithium polymer battery with non
LiPo charger. something\'s on fire.
Since this is not a guide to purchase, I will not discuss specific Charger models or suggestions, but I would say that 90% of LiPo chargers use the exact same UI and are basically the same internally.
Let\'s compare the two chargers and discuss the specifications and differences: charger 1: Dynam Supermate DC6Charger 2: Thunder ac6 power input-
Due to inefficiency, you need to provide more power to your charger than it outputs.
My Thunder AC6 can be inserted directly into the wall because it has an AC adapter built in and the Supermate DC6 needs an external PSU (
Thunderbolt AC6 can also be powered from the external PSU, but it doesn\'t make much sense for home use).
Both Chargers have a maximum output of 50 w, which means they need more than 50 w inputs. . .
Say at least 60 W, maybe a little more certain. Power Output -
As I said, both Thunderbolt and Supermate have a maximum output of 50 w.
Keep in mind that wattage is a product of voltage and current, so the maximum current you use to charge the battery depends on the voltage of the battery and vice versa.
However, in addition to the wattage limit, the charger has a maximum/minimum voltage and a maximum/minimum current output.
The current output range of both chargers is 0. 1-5.
Voltage range of 0A and 1-6S for LiPo (4. 2-25. 2V charged).
This means that while you can charge the 2 s battery at a rate of 5A (8. 4V*5A=42W)
, You will not be able to charge the 3 s battery using the same current (12. 6V*5A=63W).
For 3 s batteries, the maximum charging current on the 50 w charger is 3. 9A(50W/12. 6V=3. 968A). Balancing -
Balancing the battery is probably the most important part of charging the LiPo battery.
When using LiPo batteries, their batteries may discharge uneven and become \"unbalanced \".
\"To solve this problem, balance chargers like this plug in the balance lead and discharge lead of the LiPo battery, allowing them to charge the battery in the LiPo battery separately and\" balance \", so that all batteries have the same voltage (4. 20V, remember? )
At the end of the charge.
Some LiPo chargers do not have a balance function and in this case it is necessary to purchase and use a separate balancer.
Since I don\'t have much experience with using standalone balancers, I won\'t go into them in detail. Additional features-
Some chargers have additional features such as temperature sensing or USB connection.
Both Chargers have a temperature sensor input, which can be useful if you want to stop charging the battery when the temperature exceeds the predetermined value (
We will discuss this later).
Thunder AC6 has USB, which works with Windows applications for data recording.
It\'s a bit cool, but it\'s not particularly necessary most of the time.
In addition to the battery and charger, you need something else to take care of your fat: Digital Multimeter-
Sometimes the voltage reading on the charger is not exactly accurate, so it is good to always be able to go back to a reliable multimeter to verify.
When I use the new LiPo battery, after I remove each battery from the charger, I always check its voltage with a multimeter to make sure it is charging correctly.
Low voltage alarm/cut-off-
These batteries are used with your LiPo batteries when they are discharged.
Low voltage alarm or cut-off, or more common LVC, plug in the balance connector on the battery and monitor the voltage of each battery.
When any battery below the safe voltage (
This threshold depends on LVC, but usually between 3. 3V and 3. 0V)
, LVC or LVA will alert you with lights and/or buzzer or cut off the power supply to prevent further discharge.
Electronics that intend to run out of LiPo batteries usually have this feature built in
In, but if you are using LiPo that is not designed for it, you need to use one of them or something like that.
Charging Box/package-
LiPos should not be charged in open space for security reasons.
If something goes wrong inside LiPo, it shoots a flame from it and it\'s easy to ignite anything.
Most people charge their own fat in LiPo bags, which are padded fire-resistant sleeves that can drain smoke but keep the flame inside.
However, I prefer the cartridge method, mainly because it looks cooler and scares people.
I am charging in the open air for the purposes of this note, but I will never do so, because keeping fat safe while charging is probably the most important thing you can do.
Charging LiPo batteries, especially balance charging, is a very accurate process.
Something bad happens if you get it wrong, but luckily the LiPo charger will do its best not to catch fire.
When the charger is set up to balance the charge of the LiPo battery, you will see two main parameters: current and voltage. Charging current-
The current you should charge the LiPo battery depends on the capacity of the battery and the charge C rating.
However, regardless of the charge level C, most people charge at the speed of 1C, because this is the safest speed from the perspective of fire hazard and battery life.
Charging LiPo at a higher speed will make it faster, but in the long run, high-speed charging will also reduce battery life. Charging voltage-
This is the nominal voltage of the battery you are going to charge.
The charger often states the battery arrangement (such as \"3S\")
Next to its nominal voltage for easy identification.
My charger checks the battery by balancing the plug to count the battery, and if the voltage you choose does not match the voltage of the battery, it does not charge, which is a very good safety feature.
Here are some real things.
Life LiPo balance charging scene: 2600 mAh 3 s LiPo is charged under 1C1C * 2. 6Ah = 2.
6A charging current 3*3. 7V = 11.
1 V charging voltage. 6A*12. 6V (
Full charge voltage)= 32.
7 w power draw1800mAh 2 s LiPo is charged at 1C1C * 1. 8Ah = 1.
8A charging current 2 s * 3. 7V = 7.
4 V charging voltage 1. 8A*8. 4V(
Full charge voltage)= 15.
12 w power draw5000 mah 2 s LiPo charged at 1C1C * 5. 0Ah = 5.
Charge current 2 s * 3. 7V = 7.
4 V charging voltage. 0A*8. 4V (
Full charge voltage)= 42.
00 W power draw all these charges of their respective batteries are very safe and within the capacity of the charger.
In addition, since these charges are carried out at the 1C charging rate, it theoretically takes 1 hour to charge each battery from 3.
00 v \"dead\" to 4 per grid.
20 v per grid.
\"In real life, the charging time varies depending on the degree of discharge of the battery (
Most of the time, you will stop using the battery before it reaches 3. 00V/cell)
And the degree of imbalance between cells (
The more unbalanced they are, the longer the charger will balance them).
For further instructions, let\'s take a look at the same battery, but this time it\'s 2C: 2600 mAh 3 s LiPo charged under 2C2C * 2. 6Ah = 5.
2A charging current 3*3. 7V = 11.
The charging voltage is 1 v. 2A*12. 6V (
Full charge voltage)= 65.
52 W power draw1800mAh 2 s LiPo charged at 2C2C * 1. 8Ah = 3.
6A charging current 2 s * 3. 7V = 7.
4 V charging voltage. 6A*8. 4V (
Full charge voltage)= 30.
24 w power draw5000 mah 2 s LiPo charged in 2C2C * 5. 0Ah = 10.
Charge current 2 s * 3. 7V = 7.
4 V charging voltage. 0A*8. 4V (
Full charge voltage)= 84.
00 W power draw we can see that my own charger is not able to charge 2600 mAh 3 s battery and 5000 mAh 2 s battery at 2C, but there are a lot of other chargers.
2C charging means that in theory it takes only 30 minutes per charge.
Never charge the battery at a speed higher than expected.
Even so, I still don\'t recommend charging any battery above 1C, regardless of whether it\'s rated for 1C or not.
If your battery is capable and you are in a time-pressed situation, you can do this, but repeat charging at a higher C rate will be faster than charging at a lower C rate.
After you set up the charger for the LiPo to be charged, it\'s time to plug in all the cables on the battery side.
Plug the balance adapter into the charger and the balance lead of the battery into the appropriate slot on the balance adapter (
It is only suitable for the one made for its cell count).
Then insert the charging lead of the charger into the discharge lead of the battery.
Depending on the charger and its accessories, it may be plugged into the battery in a different way.
In my case, the charger comes with a variety of banana plug leads.
I conveniently misplaced the lead wire attached to the battery plug (
Called Deans Super plug)
, So I had to use a different plug on the lead of the charger and run the adapter between the charger and the battery. . .
Once everything is plugged in, start charging your LiPo.
Like I said, after I told my charger to boot it will check the battery of the battery and ask me to confirm my settings before charging so your battery may also
LiPo charger follow 2-
Parts are processed, using the \"constant current\" technology first, followed by the \"constant voltage\" technology.
In the \"constant current\" section of the process, the charger rises to its specified amp output and keeps the amps constant as the battery voltage rises.
The charger switches to \"constant voltage\" when the battery reaches a certain threshold \".
\"In this section, the charger changes the current output to keep all the batteries of the battery at the same voltage.
Balance occurs during this part of the charging process.
The current drops significantly as the charger approaches completion until the battery is fully charged at 4.
20 v per battery, the charger stops at this time.
Pay attention to the temperature when your LiPo is charging (
I told you I \'d come back! ).
LiPo should not work more than 90-
100 degrees Fahrenheit when charging.
If it does look hotter than this (
You can feel it by hand, read it with the temperature sensor of the charger, or use an infrared thermometer)
Stop charging immediately.
In my charger, I can set the charger to power off the battery at a temperature threshold.
If you are not going to use your LiPo for a long time (
Several weeks and more than a month)
It is a very good idea to store correctly.
The first step in LiPo storage is to charge/discharge it to the appropriate storage voltage.
Like all other battery chemicals, LiPos will do it on its own
But at a very low rate.
If there is no discharge, LiPo can discharge further below the safe voltage range, so it\'s useless and dangerous the next time you want to charge.
If you keep fully charged, the cells in LiPo will soon be out of balance.
The appropriate storage voltage for LiPo is 3. 85V per cell.
Most LiPo Chargers have a storage function that can charge or discharge the battery until it reaches 3. 85V per cell.
Because the discharge range of my charger is 0. 1-1.
0A, the maximum storage charging rate is 1.
0A, so I set it as close to 1C as I can (
It\'s usually full 1. 0A)
And set the voltage according to the battery I want to store.
After your LiPo is at the appropriate 3 points.
85 V per unit for storage, ideal for your stay.
Fat is best stored at a relatively low temperature (40-45 degrees F)
So the fridge is a good place for them.
It\'s a good idea to still protect the stored battery in the event of a fire, so I would suggest putting the fat in the profit pocket and putting the profit pocket in the refrigerator.
However, the refrigerator is not the only place to put fat.
Low humidity, reasonable temperature is enough.
In some cases, you need to drain your LiPo completely.
The most likely reason is to measure the capacity as charging starts from 3.
0 v to 4 per cell. 2V per cell (
Or from 4.
2 v to 3 per community. 0V per cell)
Is the only way to accurately judge the ability.
As I said in the last step, the maximum discharge current of my charger is 1.
0A, so that\'s how I use it when discharging most of the fat, unless they\'re really small (
I use my LiPos to draw 25-on duration-
75A, so 1A is not a problem for my battery).
Recall the constant C rating of the battery discharge, as close as possible to its maximum constant discharge current.
For the reasons mentioned in the last step, do not let your fat fully drain for a long time, otherwise you may not be able to recharge again.
It will take care of you if you take care of your LiPo battery.
Or at least don\'t burn your house down.
Here are some guidelines for safe use of LiPos :-
Don\'t poke it, don\'t poke it.
There will be a fire. don\'t drop it.
There will be a fire.
Don\'t shorten it.
There will be a fire.
Don\'t overcharge.
There will be a fire.
Don\'t let it overheat.
There will be a fire.
Don\'t throw it into the fire.
Leave more jokes aside and follow the instructions that come with the device. you should be fine, but always be vigilant.
Avoid leaving the charger when it works on your LiPo, because if something goes wrong, it\'s a good thing to have it right around. . .
Or at least less wrong.
For a good experience with these batteries, one of the most important guidelines is to always work within LiPo\'s electrical capabilities :-
Constantly monitor the voltage of each unit manually, or better yet, automatically monitor the voltage of each unit with LVC or something like that --
Match the components in the project to make sure you never take too much up to date information from the LiPoI plan and add more information and answers to people\'s questions.
Please rate and comment on this note during this period.
I hope it will provide some useful insights into the field of lithium polymer!