Li-Po batteries are truly God’s gift to RC. Lighter, more powerful and essentially more efficient than their predecessors and counterparts, they are the joy of every RC hobbyist; treat a Li-Po battery well, and it will serve you faithfully. That’s easier said than done, though. It’s to be hoped that you’re not reading this because you’ve already had bad experiences, but many of us find out the hard way that these are temperamental beasts! So how do you avoid the pitfalls of Li-Po battery use, and make sure you have a long and happy relationship with your current packs? Well, we’re here to let you in on the secrets.
Let’s start with the basics of their care. We’re talking keeping them clean and dry, out of contact with any random metal objects and at safe, non-extreme temperatures. To get these criteria down, you want to make sure they are properly encased and sealed when in your RC vehicle/craft, preferably in a waterproof battery box or a homemade version of one (although this is a must for boats!), and stored in a clean, dry place when out of it. You might also want to give the contacts a quick wipe with a cotton swab and alcohol (no, not the drinking kind) every now and again, to make sure they’re squeaky. Apart from that, making sure your vehicle/craft doesn’t overheat and avoiding carrying them in your pocket along with your keys should do the trick!
That’s all common sense, though, and there are plenty of other traps that Li-Po users fall into that decreases the life of their batteries. Running them down too much is a big one, especially in electric vehicles, where a battery death will cause the model to do nothing worse than come to a halt. It’s tempting, but don’t do it! Li-Po batteries should stop being used when the model they’re powering begins to slow, and not too long after.
“But what about discharging?” I hear you say. Yes, if you know anything about battery discharging or cycling, it can seem like conflicting advice. For those not in the know, battery discharging is using a specialist unit to deliberately drain the batteries of power, and cycling is when this is alternated with charging so that the batteries are filled and drained several times; for complex scientific reasons, this can help to prevent a decline in battery capacity. So what’s different about draining the battery in the model? It’s a case of controlled environment – basically the charger/discharger will stop at a safe minimum charge level. The model won’t!
That said, battery discharging and cycling is a vital part of Li-Po care. It’s recommended that you ‘break in’ new Li-Po batteries by cycling them a couple of times through, to help recover any capacity lost while they were in storage waiting to be bought. After that, you should do it every couple of weeks to combat a phenomenon known as ‘memory effect’. This is is the term used when the battery appears to ‘remember’ how far it was last discharged, and shrinks its capacity accordingly. Fully discharging helps to ‘wipe’ this ‘memory’ from the battery, and starting to do this early on will let you save more of your battery’s capacity from extinction.
The other thing you need to watch out for with Li-Po batteries is making sure that the individual cells within the battery are balanced. You can check this using the ‘taps’ (individual power points on each cell), and a specialist charger will let you charge or discharge cells one by one, so that you can achieve the most even charge possible. This really is a safety issue as well as an efficiency issue, since Li-Po battery packs with more than a 0.1V difference between the cells are in danger of exploding! Which really wouldn’t be maintaining your battery very well, would it?
Other tips include avoiding overcharging your batteries too; not a problem if you have a specialist charger (such as the ever-popular iMAX B6AC from Sky RC), which will remember your battery’s settings and cut out the charge before it begins over-charging, but simpler chargers need to be used with care! Our advice is to get yourself a dependable unit like the B6AC whatever your level of commitment is, as they make it so much easier to look after your batteries’ health.
Lastly, well, don’t be too ambitious in what you try and get your batteries to do. They are temperamental and volatile things, so if you’re not certain of something, then don’t experiment! This goes for things like series charging, using other batteries in a model than what it was designed for, etc. It can be done, but only with great care and attention.
Use these tips to look after your Li-Po batteries, however, and they should see you enjoy longer run times, better battery safety and longer battery lifespans, which in turn gives you a healthier wallet! And if that stuff isn’t worth putting in the effort for, we don’t know what is.