Li-Po batteries maintenance

This post is your go-to guide, designed to help beginners navigate the essentials of Li-Po battery maintenance and hygiene, ensuring your flights are not just exhilarating but also safe.

TL;DR —

• Store at ~80% charge
• Never discharge below 20%

Lithium Polymer (Li-Po) batteries

Li-Po batteries are the lifeblood of FPV drones, favored for their ability to store large amounts of energy in a lightweight package, and able to discharge that energy quickly. This makes your drone agile and responsive, capable of impressive feats in the air. However, their chemistry also makes them more volatile than wide spread Li-Ion batteries. Understanding the temperament of Li-Po batteries is the first step towards harnessing their power safely.

To put it simply, Li-Po batteries 🔋 burn 🔥 hot and fast when things go wrong.

Basic Maintenance Tips

Storage

Li-Po batteries charged to 100% and not used for 1-2 days will degrade faster and can swell. Store them at ~3.8V per cell. So 4S battery should be stored at around 15.2V (3.8V * 4 cells).

Charging

Use a charger specifically designed for Li-Po batteries, and never leave them unattended while charging.

Cheap charges can be dangerous as they can overcharge the battery and/or overheat itself with the similar consequences. Overcharging is a big no-no, as it can lead to fires.

Patience is a virtue; charge at a moderate rate 🔌 to prolong battery life.

A fireproof charging bag is a small investment for peace of mind. Search for "Li-Po safe" or "Li-Po fireproof bag".

Discharging

Never discharge a Li-Po battery below 3.0V per cell. This can cause a battery to die on the spot, and extreme discharge definitely will reduce the battery's lifespan.

Handling

The drone would often crash on a battery, so it's important to check the battery for any damage after a crash. If the battery is punctured, swollen, or damaged in any way, it's best to retire it not risking turning your drone into a blazing fireball.

Avoid extreme temperatures, both hot and cold, as they can damage the battery, and don't leave them in direct sunlight.

Gear

Avoid cheap chargers and batteries. You risking your drone and your home. A good charger could not only charge but also discharge and balance the cells. It's a good idea to have a charger that can charge multiple batteries at once.

4-6S Li-Po Battery Charger

iMax B6AC — avoid 🚫

I saw this reddit post about burning Li-Po batteries and in the commnents they named iMax B6AC as the culprit.

I bought my Mobula 7 from a guy who burned four 1S batteries with the same charger. I saw V2 of the charger on the market, but I'm not sure if it's safe to use.

HOTA D6 Pro — recommended ✅

Everyone and their dog recommends the HOTA D6 Pro charger. Disclaimer: I don't have it, so do your own research.

Here is a review by Matt Pochwat:

1S Tiny Whoop Li-Po Battery Charger

Whether to use a dedicated charger for 1S batteries or a "grown-up" 4-6S charger with a parallel charging board is a somewhat polarizing topic. I don't have enough knowledge about batteries chemistry but if you plan to fly only Tiny Whoop, then 1S charger is 3-5 times cheaper than a big one.

Betafpv 6 Ports 1S Battery Charger — on a tight budget

I bought the Betafpv 6 Ports 1S Battery Charger and it's a good charger for the price. It can charge up to 6 batteries, both BT2.0 and PH2.0 connectors. It has a USB-C input, so you can use a power bank to charge the batteries on the go.

I had to return it because it doesn't have discharge function, and it was a deal breaker for me. I would charge multiple batteries, fly one, and then got to do something else, or the weather changed, and I had to discharge the batteries with the drone at home to store them safely.

VIFLY WhoopStor 3 1S Battery Storage Charger and Discharger

I own the VIFLY WhoopStor 3 1S Battery Storage Charger and Discharger now and I love it. It can charge and discharge up to 6 batteries at once, meaning I don't have to care which battery is charged and which is discharged — put all of them in and press the button. It also has USB-C input, and BT2.0 and PH2.0 connectors, Additionally, it has XT60 input, so one could use 2S-6S battery to charge 1S batteries.

It can handle 6V-26V (XT60 2S-6S Battery, DC), or 9V-20V (USB-C), in case you are in a hurry and want to charge faster, you can use more power (for the price of battery life).