LiPo batteries are the most popular, efficient power source for RC vehicles. However, they can be extremely sensitive and volatile, making storing them safely challenging.
The best way to store LiPo batteries is at room temperature, in a dry place where there will be no dramatic fluctuations in temperature. LiPo batteries can be a fire hazard, so store them in a fireproof bag or cabinet, away from any flammable materials.
Despite the improvement in performance that LiPo batteries brought to the hobby, there’s a steep learning curve to knowing how to properly care for them.
This article will detail how to care for and store these batteries so you can maximize their lifespan.
RC LiPo Batteries: Overview
LiPo batteries were a significant leap forward in battery technology for RC vehicle operators. They were created by Sony in 1983, and the technology has improved dramatically over the years.
LiPo, or Lithium-ion Polymer batteries, are also sometimes known as Li-poly, LIP, and lithium-poly, among other names.
Lithium-ion batteries are lightweight and can be made in different shapes and sizes.
This allows manufacturers to have batteries shaped to their designs rather than designing their product around the battery.
The downside of LiPo batteries is that they are relatively sensitive, requiring care in their maintenance, use, and storage to ensure safety and performance from these batteries.
Where Should LiPo Batteries Be Stored?
LiPo batteries should be stored in a temperature and humidity stable location. Fluctuations in temperature from very hot to very cold degrade the battery’s internal chemical makeup and severely dimmish its lifespan.
Do not store LiPo batteries on a shelf in the garage, where the temperatures can range from high during the day to low temperatures at night.
Temperature fluctuations can damage the chemicals in the batteries, causing them to lose their ability to hold a charge. This can potentially result in a battery fire from an internal short circuit.
Damaged or old LiPo batteries are a fire hazard and can explode or catch fire in certain conditions. If a battery is past its usable life, discard the battery correctly rather than throwing it in the draw with your other batteries.
Always store LiPo batteries away from anything that could catch fire should the battery spontaneously combust!
LiPo batteries should not be stored in a location exposed to direct sunlight or where they will be exposed to extreme cold.
Some people advocate storing LiPo batteries in the refrigerator, but this is not recommended.
Storing a LiPo battery in cold temperatures can cause multiple problems for the battery, many of which can result in a battery fire.
As the battery warms up, condensation can build up inside the battery’s packaging, which can also cause a short circuit, resulting in a battery fire.
The best place to store LiPo batteries would be in a fireproof container and a separate drawer or cabinet from where you keep your other RC equipment.
Should You Charge Should LiPo Batteries Before Storing Them?
Historically, RC vehicle operators would use batteries in their vehicles until the battery died. Then, you’d simply store the battery until you needed it.
This isn’t recommended for LiPo batteries, however.
After use, LiPo batteries should always be ‘maintenance charged’ or ‘storage charged.’ They should not be stored completely discharged or fully charged.
The recommended charge for storing these batteries is at a voltage of 3.8V for each cell in the battery. This is often referred to as the storage voltage for the battery.
This voltage is the midway point between a fully charged battery of 4.2V per cell and a flat battery at 3.3V per cell.
Always keep an eye on your battery while charging it. Leaving it on the charger for an extended period can be a safety concern and detrimental to the battery.
It is also recommended to use balanced battery chargers with constant current constant voltage charging capability, often referred to as CC/CV chargers.
These chargers help prevent overcharging the LiPo batteries, generating heat, leading to a battery fire.
Most LiPo batteries come with a datasheet that will specify the best storage voltage and temperatures for the batteries. It is good battery management to store your LiPo batteries within these parameters for the best longevity of the battery.
Manufacturers produce fireproof LiPo Safety Storage Bags as an extra safety measure for storing these batteries. We highly recommend investing in safety storage bags, especially if you keep multiple batteries in the same location.
If one battery should catch fire, it can set nearby batteries on fire, quickly progressing into a life-threatening fire or explosion.
What Temperatures Should You Store LiPo Batteries?
LiPo batteries are negatively affected by excessive heat and by freezing temperatures. These extreme conditions degrade the battery components and limit the battery’s time to successfully hold a charge.
It’s best to store LiPo batteries at room temperature (between 68°F to 72°F or 20°C to 22°C).
That allows batteries to be immediately charged or plugged into your RC vehicle without waiting for them to warm up to room temperature.
Either way, slight temperature variations shouldn’t be detrimental to the battery’s condition. However, be sure to avoid sudden temperature changes.
How Long Can LiPo Batteries Be Stored?
LiPo batteries retain their charge on the shelf much longer than batteries using other technologies to store charge.
The batteries can theoretically be stored on the shelf for up to 4 years. Still, a more realistic storage timeframe is between 18-months to two years.
LiPo batteries will lose up to 5% of their charge each month, so don’t put a LiPo battery into long-term storage and expect it to have a full charge when you need to use it.
When storing LiPo batteries long-term, periodically check to see if the battery still has a balanced charge. Most hobby-grade battery chargers have a ‘maintenance charge’ or ‘storage charge’ setting. This prevents permanent damage to your LiPo batteries.