Introduction And Maintenance Tips For Li-polymer Batteries
Lithium polymer batteries, sometimes known as LiPo batteries, are rechargeable energy storage devices that employ polymer electrolytes rather than liquid electrolytes.
RC cars are a popular market for LiPo batteries since they require batteries to run and LiPo batteries seem to be a perfect choice.
Most notably, they outperform all of their rivals in terms of keeping a constant voltage.
How to determine which LiPo Battery is best for RC Cars?
There is a common misconception that all batteries are comparable and similar.
They may have a similar appearance and the same characteristics and configurations; however, they differ on the basis of value, performance, and efficiency.
Endeavor to do independent testing, take battery setup into account, and inspect the connections.
Furthermore, before acquiring a Li-polymer battery, be sure to read the reviews and ratings.
How do you keep LiPo batteries for RC cars in good condition?
LiPo batteries, generally, necessitate proper care and maintenance because they are a bit overly delicate and require additional attention.
Although, most people merely disregard the fact that they require maintenance because they also provide several benefits, such as being lighter, having greater capacity, better discharge rates, and more.
Here are a few pointers that can help you get more performance out of your RC car’s LiPo batteries.
Use appropriate and compatible chargers
Compatible chargers for LiPo batteries should be the top priority, and not simply because they extend battery life.
In addition to raising the safety hazards and lowering the battery’s lifespan, using an incompatible charger prevents your battery from being fully charged.
Charge properly
It is recommended that you do not overcharge your battery and keep it completely charged.
Overcharging your battery beyond 4.2 V per cell is not recommended.
Using a suitable charger will also assist you in maintaining the current and voltage levels till it reaches their optimum level.
Charge it in accordance with the directions, please. Avoid charging them near combustible surfaces or at below-freezing temperatures.
Frequently inspect your battery to make sure it is not bloated, fractured, or otherwise compromised.
Discharging
Batteries should not be discharged beyond the labels’ recommended amperage rates.
Discharging the battery below 3V may result in negative repercussions.
Also, make sure your battery‘s temperature doesn’t exceed 140 degrees Fahrenheit throughout the discharging procedure.
Storing
Even with the storing of Li-Polymer batteries, more caution and consideration are required.
Do not keep your battery fully charged if you want to store it for more than 30 days or if you intend to leave it in its current state for around a month.
Verify that loose batteries are not kept close to one another in storage. Additionally, it is advised against keeping your batteries in the direct sun, next to combustible materials, or at extremely high or low temperatures.
Disposal
Because the LiPo battery might be dangerous, it’s crucial to get rid of it carefully.
After shorting out the Li Polymer battery by submerging it in a saltwater bath, check the voltage before discarding the batteries.
General handling
There are a few general safety precautions that should be taken when handling LiPo batteries for RC vehicles, including
- Not disassembling the cells
- Never using them near combustible surfaces
- Never dispose of them in fire, prevent cell opening and deformation
Structure of a Lithium Polymer Battery
Lithium polymer (LiPo) batteries are a great choice for model aircraft for a few different reasons. Based on their chemical makeup, they are among the most powerful batteries by weight that exist. They are particularly energy dense, and have the capacity for delivery that power extremely quickly on demand. LiPo batteries use a few different components to create a charge that you can use. Understanding that structure is key to understanding how to properly perform FPV battery maintenance.
LiPo batteries use a series of alternating structures that facilitate the transition of electrons from one layer to the next. These layers, the cathode and anode create a pathway for charge to flow. The cathodes use aluminum and is coated in an oxidizing lithium material. The anodes use a copper material along with a carbon material, such as graphite. The anodes and cathodes alternate between a micro porous polymer membrane, the separator. The entire structure is suspended in a lithium gel electrolyte. Lithium itself is highly reactive to both air and water, and when the battery has a puncture or cut, can cause a fire.
When a battery is charged, the cathode passes lithium ions through the electrolyte and separator, to the anode, where they are stored for use. This gives your battery it’s “charge”. When discharging, the process is reversed; the anode passes the lithium ions back to the cathode, and that charge is pumped into your model for use by your electronics.
Internal Resistance
One of the primary indicators of battery heath is going to be the internal resistance of the battery. Generally measured in term of milliohms (mΩ), the internal resistance of a battery determines how hard it is to pass the energy stored in the battery to the model aircraft. The higher the internal resistance, the harder it is to pass that energy.
During use of the battery, there are many things that can cause internal resistance to rise. When you deep discharge your battery (take it below the 80% discharge level), that can cause internal resistance to rise. Also, when pushing the battery to pump out maximum energy over an extended period of time, can affect internal resistance negatively. Batteries over time will naturally build up internal resistance. Lastly, excessive heat can also adversely affect internal resistance. When internal resistance becomes too high, there comes a point where the battery will stop delivering all the potential energy that it was originally capable of. At this point, you may need to remove the battery from service.
When selecting a charger, you may want to look for one that can measure internal resistance. In this way, you can be up to date on the health of your batteries. If your charger does not monitor internal resistance, there are devices out there, called ESR meters that you can use.
Internal resistance is one the primary concerns when we are discussing FPV battery maintenance. When you don’t take the time and care with your batteries, their life span, and your investment, will be cut short. Believe me, I have experienced this firsthand.
Proper Charging
Proper charging protocols are the beginning of excellent FPV battery maintenance. When charging your batteries you want to take a few things into consideration. First, would be the capacity of your battery. Capacity is defined by how much charge your battery can both store, and deliver, and is rated in amp hours, or Ah. Because of the size of our batteries, that is often reduced to milliamp hours, or mAh. One of the most common capacities in use for multirotors would be the 1300 mAh battery, and as such will be the one that we will be using for our example.
What Amp Setting to Use?
When determining the proper amperage to charge a battery, one will directly reference the capacity. You will often here pilots talk about what “C” they charge their batteries at. You can determine “C” rating in amps by using the following equation; cA = mAh / 1000. In the example of our 1300 mAh battery, this equates to 1.3 amps. So now, when someone talks about charging their 1300 mAh battery at 2C, you can calculate that out to be 2.6 amps, using this equation; 2(cA) = (1300 mAh / 1000).
Most batteries will alert you to the maximum rate that you can safely charge your batteries at, either on the battery, or with the included documentation. For example, the Lumenier Batteries are rated at a maximum of 5C charge rate. Now, the question is, does that mean that you should always charge your battery at this rate? Absolutely not! Charging a battery at that rate will accelerate the decay of the battery, and raise your internal resistance quicker. Charging batteries is similar to creating good barbeque; low and slow. The recommended charge rate for any battery is going to be 1C. Charging at 2C should be the highest you go, and only if you are in a hurry.
Don’t Walk Away!
On a safety note, never leave your charging batteries unattended. The hobby is rife with examples of LiPo fires taking out a pilots gear, garage, or entire home. Even with someone paying attention, these things can happen, but by being around your batteries when charging, you can react to a situation much quicker. Proper FPV battery maintenance always starts with good safety practices.
Parallel Charging
Parallel charging can be a way to get several batteries charging at once, but use with caution. The way parallel charging works is by using a charging board specially designed to accomplish this task. When several batteries are hooked up to the board, the charger sees them as one large battery. In order to charge these batteries at the same rate as you would a single battery, you need to do a little more math. In our example, we are going to use the 1300 mAh battery again, and we are going to charge six of them together using a parallel board. Using this equation, we can determine what 1C is; cA=6(1300 mAh / 1000). From this equation, we get 7.8 amps. Now if we wanted to charge at 2C, it would look like this 2(cA) = 6(1300 mAh / 1000), resulting in 15.6 amps.
The Do’s and Don’ts of Parallel Charging
There are three things to consider about parallel charging when considering proper FPV battery maintenance. Firstly, never charge batteries that have a different number of cells together. For example, do not charge 3S batteries with 4S batteries. Doing so will damage your batteries, might damage your charger, and may start a LiPo fire, which we should avoid.
Secondly, batteries that are to charge together need to have very similar voltages. Optimally, they need to be within.10 volts from each other. If they are not, you may need to “bump” charge them to get them within that range. Not heeding this advice can lead to batteries with a higher charge dumping that charge into the lower charged batteries and a very fast rate, damaging both.
Lastly, and most important, internal resistance rears its ugly head here. Think of internal resistance as a virus that infects your batteries. That virus can “transmit” to your other batteries through the parallel charging process. So if you have a bad battery, and you charge it together with other batteries, you can corrupt all the other batteries.
I’m not going to tell you not to parallel charge, but ultimately if you want to make sure you don’t corrupt your batteries, or don’t want to have worry about matching voltages, you may want to look into a multiport charger. It’s truly the safest option out there.
How to Prolong the Lifespan of a LiPo Battery
The essence of buying a LiPo battery is that you need a battery with long run times. While LiPo batteries may offer a lot of benefits, when misused it’s just a waste of money.
The big question is how to maximize the lifespan of your lithium polymer battery, and we’ll answer that now!
Proper Storage Mode
When it comes to LiPo batteries, there’s something called “storage mode”. It’s possible that after using your LiPo battery, you may decide to keep it for later use, but unlike other batteries, you don’t just casually put LiPo batteries in a drawer and expect the power capacity to remain the same.
With LiPo batteries, you need to store the battery pack properly if you intend to prolong its lifespan. You can decide to do this process manually if your charger doesn’t have a defined charging mode to store the pack.
Every battery pack comes with a voltage pack, and this is how you can tell the best storage specification for your LiPo battery.
Your battery capacity is usually 40% at the right storage voltage, and the voltage of a battery pack is 3.85 volts.
When you keep your battery at maximum charge when not in use, it drains it faster than you can imagine, also leaving it almost drained isn’t the best option either.
To maximize the lifespan of your Li-Po battery, ensure that you stick to the storage voltage specification.
Use LiPo Compatible Chargers and Don’t Overcharge
You can’t expect a 3 charger to get your LiPo battery to full charge without overcharging or overheating it.
There are lots of battery packs that claim to offer over 10C charge rates, and that’s absurd because you’ll end up with a damaged LiPo battery in no time.
3C charging has a great speed, and to optimize the health of your LiPo battery, it’s even advisable to opt for 2C charging. Some people even charge at a 1 C rating and they have no complaints about the lifespan of their batteries.
Normally, LiPo batteries get unbalanced when charged with cheap charges, and this can cause them to have different voltage values.
To get the best out of your LiPo battery, you need to invest in a LiPo-compatible charger.
The highest voltage your fully charged LiPo battery can attain is 4.20 volts, and it’s not even advisable to recharge to this point, as it reduces the lifespan, so it’s best to charge below that.
In the case of LiPo batteries, the lower you go below the 4.20 volts mark, the longer your battery’s shelf life.
Knowing The Right Time to Charge
For LiPo batteries, you need to know the exact time to plug them in, or you’re at risk of damaging them before enjoying their benefits.
Remember that the lifespan of a LiPo battery is 300 to 500 charge cycles, but there’s no point waiting to charge it after the battery life is completely drained.
Charging your LiPo battery before it’s completely drained is a sure way to maximize its lifespan. Whenever you get the chance to plug in your battery, please do.
Unlike other batteries, LiPo batteries don’t care if they are being charged a hundred times, so don’t fret about damaging them from too much charging. Make sure you are using the right charger and you are charging at a decent charge rate – 1C or 2C.
Temperature Check
LiPo batteries are sensitive, so you aren’t advised to toss them around anywhere and go about your day.
Do you know leaving your battery under the sun can permanently damage it? Heat is a huge spoiler when it comes to LiPo batteries, and they won’t charge well in hot environments.
Storing your LiPo battery pack according to the ideal storage specification without keeping it in a cool place is a disaster.
So, make sure your battery has cooled down to a moderate temperature before using or charging.
Know The Maximum Discharge Time
When we talk about maximum discharge rating, this is the highest power capacity you can use out of your LiPo battery. You may be wondering why you need to follow any discharge rule, after all, you are supposed to enjoy your battery until it gets depleted.
Unfortunately, that is not the case with LiPo batteries; remember the plan is to make sure your batteries last as long as possible.
So, if you are still on that track, the best way is to allow your battery pack a run time of 80% or less than that. There should always be at least 20% capacity in your battery pack before charging.
How to Check for a Damaged LiPo Battery?
LiPo batteries are expensive, yes; however, it’s still not an excuse for you to keep using a damaged battery. Everyone wants a battery that can last for many decades, but that’s impossible, and with a LiPo battery pack, it’s best to know when it becomes damaged so you can carefully dispose of it.
The most common way of knowing your LiPo battery is damaged is when it doesn’t supply power to your RC devices anymore. There are other signs you need to look out for, so you can immediately dispose of your battery when it gets bad.
- If you are noticing an unusual electrolyte smell emanating from your LiPo battery, there’s a high chance that it’s damaged already. A leaking electrolyte is dangerous to even your devices because it’s acidic, plus electrolytes are highly inflammable.
- Noticing dented corners around your LiPo battery pack? If yes, it has gone bad.
- When it comes to all types of batteries, puffiness is bad news. So, if your LiPo battery is puffy, you need to stop using it ASAP!
- Visible damage on the body of the battery is likely a sign that it’s already damaged.
Important Information Every LiPo Battery Owner Should Take Note Of
LiPo batteries are great investments and last for a long time when handled with care. Yes, there are risks involved with using them, but the benefits far outweigh that. LiPo batteries are common, plus their battery cell has up to four times the energy of normal batteries, so why shouldn’t you go for it?
Remember, with LiPo batteries, you don’t over-charge or over-discharge.
Battery Storage
- You’ll need to recharge your batteries up to 50% at least once every 6 months if you’re storing them for a long period of time.
Remove the battery from its device before you store it. If you’re storing an electronic device, take out the battery first. Otherwise, the battery may drain faster. Similarly, the battery may leak over time, which might damage your device. Always store them separately. [17] X Research source
- For instance, you might place them in a hall closet or a dresser drawer.
- Don’t store your batteries in a hot kitchen, attic, or garage.
Use the batteries within 6 months of storing them. Lithium batteries can go completely dead if they’re left unused. Don’t leave your batteries in storage for longer than 6 months at a time. Otherwise, they may stop holding a charge. [20] X Research source
Tip: To keep track of when you stored your batteries, use a marker or pen to write the storage date on the storage container.
Community QA
It’s not optimal, but it’s not as damaging as letting the battery go below a 30% charge. Keeping it between 80% and 30% is ideal.
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This is generally a sign that your battery needs replacement. If you know your battery is healthy, but you’re still running through a charge in 50 minutes, you may have downloaded an ill-behaved app that is burning through your battery. On Android you can go to SettingsGeneralBatteryBattery Usage to see what app is consuming your battery and uninstall it if it is unneeded. If you can’t identify the culprit, consider doing a backup and reset.
Thanks! We’re glad this was helpful. Thank you for your feedback. As a small thank you, we’d like to offer you a 30 gift card (valid at GoNift.com). Use it to try out great new products and services nationwide without paying full price—wine, food delivery, clothing and more. Enjoy! Claim Your Gift If wikiHow has helped you, please consider a small contribution to support us in helping more readers like you. We’re committed to providing the world with free how-to resources, and even 450 helps us in our mission. Support wikiHow
It could be that the contacts on the battery are dirty or are fouled. Get a clean Q-Tip and gently rub the contact until it appears clean. Do not use gasoline or any cleaning fluid!
Thanks! We’re glad this was helpful. Thank you for your feedback. As a small thank you, we’d like to offer you a 30 gift card (valid at GoNift.com). Use it to try out great new products and services nationwide without paying full price—wine, food delivery, clothing and more. Enjoy! Claim Your Gift If wikiHow has helped you, please consider a small contribution to support us in helping more readers like you. We’re committed to providing the world with free how-to resources, and even 450 helps us in our mission. Support wikiHow
Charging/Discharging Cycles
Li-ion batteries can handle hundreds of charge/discharge cycles. The discharge rate of these batteries in idle state is relatively lower than other rechargeable batteries. Generally this battery, being inactive, can store their charge for a duration of months, while other rechargeable batteries lose up to 4-5% of their charge per day. So once charged, this battery can keep mobile phones alive for a longer duration.
The discharging rate of these batteries is dependent on their operational and storage temperature. The higher the temperature, the greater the discharging rate. One should always store this battery at lower temperatures to increase its discharging cycle.
Can You Overcharge Your Lithium-ion Cell Phone Battery?
As has been seen, the regular recharging of a Li-ion or cell phone battery is a basic redox reaction that causes lithium ions to travel from the negative (cathode) to the positive (anode) electrode. Li-ion batteries can be recharged a number of times, but eventually, after a number of charge discharge cycles, this battery will need replacement, too.
It is important not to overcharge the cell phone battery, or to let it drain out completely. If it runs out of charge completely, it will spoil the battery cells, so it is required to plug it in the charger while it still contains some charge. Furthermore, if you overcharge the battery, it creates heat which could be a fire hazard, or even cause a fire itself.
Since lithium-ion (and lithium-polymer) are sensitive to overcharging and over-discharging, the cells that make up the battery pack are charged independently. With NiMH and NiCad packs, the standard charging phenomena is to provide a current and voltage to cells connected in series so all the cells receive the same amount of current. The cell voltages in that case are not necessarily equal, in fact it is almost certain that they are not, but the voltage across the battery pack will be the same. Since NiMH and NiCad relatively show resistance to overcharging, there is usually no danger. It is common for one cell in a NiMH or NiCad battery pack to be dead without an effect on the charging of other cells. What does that mean? Let me explain it with an example.
Let’s suppose that we have a 6-cell battery pack, with the nominal voltage of each cell being 1.2 Volts (7.2 Volts total). If a charging voltage of 5 Volts is present, each cell would ideally receive 0.83 Volts approx. If one cell is dead, the voltage across each cell would be 1 Volt. That means a 20.5% increase after the death of one cell. This percentage increase is catered to by most Nickel-based cells, but a 20.5% overvoltage to lithium cells would ultimately result in a failure, and likely a fire. Li-Ion/Li-Poly batteries cannot tolerate over discharging as well, and tend to die if discharged below around 2.5 V.
How to Treat Your Cell Phone Battery
During storage, cell phone batteries, i.e. Li-ion batteries, discharge quicker if fully charged initially. So it is recommended to partially charge the battery (50-60% ) prior to storing it. It is generally recommended to recharge this battery after few months if they have to be stored for longer duration.
A cell phone battery comes with the circuitry to protect it from over-charging and under-charging, which makes it best suited for mobile phones and other handheld devices. If this battery is ever discharged below a minimum “threshold” voltage, this protection circuitry does not allow recharging of the battery, making the battery dead for future use.
This battery comes in different sizes with dedicated chargers. Using any other charger for charging this battery may pose serious danger of ignition of the battery.
And a word of caution about disposing of these batteries: they may explode if burned, so try to sell these batteries back to the battery seller as lithium-ion batteries can be recycled.