How to Choose a RC Charger

Battery chargers have always been one of the more important pieces of equipment for anyone into RC cars, and since we all moved to Lipo batteries, the chargers are even more important than before. Beginners often have a hard time knowing what to choose, and even among more experienced drivers, chargers are often not fully understood. So let’s take a look at some RC charger basics.

When one looks at what’s available you quickly realise that there’s a huge variety of chargers available. At this point, it is common to ask yourself why I should spend more on a “smart” charger when there are very affordable basic chargers out there. A basic charger can of course be a good choice if you are just getting into the hobby, testing what RC cars are about, and not sure about how much you will use your car.

What are the benefits of buying a “smart” charger then?

1. They will charge almost anything, whether it is your transmitter or receiver battery, different types of packs for your RC car, and much, much, more. Smart chargers will typically charge LiPo, NiMh, NiCd, Li-Fe, Li-Ion, and even PB batteries.

2. They will take much better care of your batteries, charging them with accuracy, for better battery safety. With accurate balancing and other advanced functions, they give you the tools to make sure your battery has a long life. In some cases, these chargers manage to charge older batteries that simpler chargers won’t, meaning batteries you thought were “dead” are brought back to life.

3. Smart chargers will display a lot of info, making sure you have a much better understanding of the condition of the battery. With the charger showing how much charge goes into the battery, and even separate cell voltages, you can easily follow and understand the condition of the battery during its life.

Because of factors like those mentioned above, a quality smart charger is very much a good investment, and in the long run it will easily pay for itself because of less battery damage and longer battery life. Batteries are not cheap, so only for that reason alone it’s worth taking care of them, not to mention the even more important point of safety.

When choosing a charger, the first thing to take into account is of course that it is compatible with the batteries you use. Since most smart chargers charge almost any type, and typically up to 6S LiPo’s, this factor does not narrow down the choice by a lot for most of us. It’s still worth confirming this when you look for a charger though.

Next we typically look for how much power a charger can deliver, and if it is enough for us. At this point it is easy to make a mistake though, as the favourite “marketing” number for chargers is power maximum charge current in amps. Amps only tell half the truth though, and it is important that you also understand and look for info on the wattage output rating of the charger. If you don’t take this into consideration, you might find yourself in a situation where your 10 amp charger don’t give 10 amp for your configuration of battery.

You calculate watts by voltage x amps. As an example, if we have a 5000mAh 2S LiPo, and charge it at the common 1C charge rate (5A for 5000mAh pack), the calculation will be 8.4 volts (fully charged 2S LiPo) x 5 amps = 42 watts. Meaning that the charger will need to be able to handle 42 watts. If we raise the charge current to 2C (10A), the calculation would be 8.4 x 10 = 84 watts. So if your charger is advertised as 10A, but 60W, it will not be able to deliver the 10A in this case.

Next to consider is what’s going to power the charger, because there are both DC (12V input) and AC (100-240V input) chargers. For any DC charger, you need a suitable separate power supply, while any AC (or AC/DC) charger you can just plug into the wall.

Some chargers have more than one output, and give you the possibility to charge more than one battery at a time. Consider if this is something you need for your use, obviously taking into account the price at the same time.

Finally, a helpful list of things to look for in a charger

• Compatibility – look for a charger that is versatile and can charge all battery types and sizes you might use
• Output – Amps and watts, remember to check for enough watts
• Quality – accuracy is important for safety and long battery life, and for performance
• Price – closely compare what quality, performance, and features you get
• Warranty – what is the repair and replacement policy
• Protection – does the charger have reverse polarity protection
• Balancer – what type of balance boards or ports included
• Charging info – does the charger show individual cell voltages etc.
• Charging cables – what cables are included, and what fits the charger