When I started with electrics (not a long time ago), I knew little or nothing about batteries. My only knowledge was related with the flight packs we put on the radio systems for our planes. Some care has to be taken with them (cycling, charging, testing) in order to keep our precious toys flying in good condition.
However, the packs that we use on the motors are a very different thing. Fast charges and high rate discharges can hurt them a lot if things are not controlled to the tiniest detail.

A good charger is a place to start. I chose a Hobbico 930 (4 to 8 cells - .1 to 5 A) and this is considered a budget fast charger. It has a couple of neat features, and I hope that the electronics inside are as good as the marketing people say they are.

There are a couple of good chargers in the market (I mean really good...) that assure a top notch care for your batteries. Tekin , Astro Flight and European makers like Graupner , Simprop or Robbe make very good (and frequently very expensive) chargers.

Some obscure makers make what they call professional chargers. My explorations on the WEB found one of them - a German manufacturer (Schulze Elektronik ) with chargers that approach the 1.000 dollars barrier.

A nice feature to have is a LCD display (or any other sort of clear display). It helps a lot setting up the current and monitoring the charge status of your packs. Almost everybody will tell you that you need Delta Peak charging. This is a capability that the charger has to detect the top voltage to which the packs go. When the voltage drops (end of charging cycle) the charger cuts off. Some of them start a trickle charge to keep the packs in full charge condition.

Some of the top end chargers include a temperature probe (cuts charge if the pack temperature goes too high), burp charging (charge, stop and restart charge cycle), discharge to .8-1 volt per cell and start charge, etc.

The deal is to look into your pockets and try to find the best match between the money available and the functionality you need. One thing is true - a bad charger ruins your batteries pretty quick.

What I learned the hard way...
(or the way to have a bad start)

If you're starting with electrics and none of your friends play with boats, and you have some doubts about the advice of shop owners, what would you do?

Probably the same I did. I ordered a couple of battery packs, Duratrax Sanyo 1500 6 cell and a pair of Sanyo 1700 6 cell.

These packs are by no means top quality, and the construction is made with metal tabs soldered on four points.

It seemed so absurd to pay 2 times the price for "matched" cells that were not even assembled ;-). Oh well, now I know that we always make some mistakes :-(.

The other wrong assumption was related with the current draw the packs were going to withstand. 20 Amps seemed too much, so I was expecting 10 minutes run time and cold packs at the end of the run (Boy, I was really wrong).

On the first couple of runs the weaknesses of the boat started to show up, leading to a couple of very frustrating days. The runs were short, the temperature of the motor and packs was very high and the mechanical Speed Control that came with the boat was not acceptable in terms of speed control.

The batteries got so hot that the shrink wrap melted and one of them was completely misaligned inside the tube. The end cap of the packs had a hole trough which you could see a blue metal tab. Solder melting on the motor and battery terminals welded together. Wow, what an experience!

I had to find information somewhere. A good place to start is a good book, so I bought one from Traplet Publications called Fast Electrics. In this book I found a lot of explanations for my problems and the way to solve them.

The first one of them was the choice of speed control (Tekin 432M). A  decent motor (Trinity Quartz 19T) and the boat became faster and more controllable. The motor cooling was installed at this time. I was not going to run any risks. Watching smoke come out of the back of the boat is not a pretty sight.

I decided to rebuild all the packs and change to a motor for 6 or 7 cells with cooling everywhere (take a look at the pictures on the Bud Light page).

The packs were all rebuilt with copper lugs and battery accessories made by Trinity.

What I've learned since then

I'm sure that everyone that starts with electric radio control vehicles has the wrong tendency to think that these things are for play. They may be, but there are very sophisticated electric vehicles. Now, I'm in the realm of electric racing cars and if you want to find a place where mystery, misconceptions and odd things may affect your performance, cars is the place to be.

And there's nothing like batteries to stir some things up.

As you can read from the previous paragraphs when I started, the black Sanyos 1700 were the batteries to have. Now we are playing with a different kind of batteries. The NiMh 3700 became the norm. And the kind of price and quality you can get are way different.

Sanyo disappeared from the scene and Panasonic was long gone. Now the players in this area are Chinese brands - GP and Intellect.

GP made an excellent battery (GP3300) the blew Sanyo out of the landscape. Cheaper, more durable and with numbers in voltage and capacity that were unsuspected just a couple of months before. They set the standard against which all new batteries are measured.

5 years ago, a matched pack would cost around 100 USD, and if you didn't take care of them they would become pieces of junk in a couple of months. Now you can buy premium packs for 70 USD and they last forever!!!

The chargers we have access to are way better then thy used to be. Programmable, updateable, and cheaper.
Competition Electronics, Orion, Futaba, Much More, etc etc make incredibly good chargers for prices we could nor believe a few years ago. Of course the needs of the average racer are now much bigger than they used to be but we have the kind of equipment to achieve them.

Matched packs are the only thing I buy now. Racing at a level where everybody has them, arises the need to have the better batteries you can get.

We can't live with a pack slowing you down in minute 4. The laps have to be in the same second all the race. No place for slower laps.
A matched pack can guarantee you this. If properly cared for it will deliver excellent performance for a long time, but the emphasis must be put in properly cared for.

How to take care of your packs

If you ask 10 different racers what to do you'll get 10 different answers.

However there are some consensual routines that you should do to your packs

• Discharge them to .9V per element

• Equalize them on a discharging tray (Noval, NOSRAM, Trinity etc etc)

• Charge them according to the matcher's instructions. Delta peak has to be adjusted depending on ambient temperature

• Never run your pack till it stops dead. This may reverse the polarity on weaker cells

• Some people defend dead shorting some people don't. What's clear is that by dead shorting the packs, the voltage goes up, IR goes down and so does run time

The way you choose to care for your packs has a crucial importance on how they perform and how they last.
A poorly treated pack wont last. Overcharging packs is the most common way of destroying good and expensive packs. Don't do it

There are a few notable items that can help you to maintain you packs in top condition.

This one is probably the bet device I've ever owned. It's called Spintec Battery Manager and is made by a very innovative Dutch company.

And how does it work?
It discharges you packs at 35Amp! However they do this in a very clever way. If you ever discharged you pack at 30 Amp you know how hot it gets and heat destroys batteries in a blink of an eye.

However this device does it by pulses. A period of discharge at 35 Amp is followed by a period of cool off time. You'll hear it!! A clicking noise comes from the pack when the discharge is taking place. At the end you pack is at ambient temperature.

A display shows you the time to complete discharge (seconds), total energy stored on the pack (Joules) remaining mili Amps, average voltage and Internal resistance.

After using it a couple of times in some packs (old and tired) I started to notice better punch on them and especially their ability to accept charge was way higher. Packs the would only get around 3300 even after traying them were now accepting 3700-3800 with ho problem at all.

On top of that, track performance was amazing with them. They behaved like new packs, although with less run time (not because of the discharging but because they had lost run time some time before). They are now my practice packs because the lap times I get with them are in line with the times I do with my new race packs!!

Excellent device indeed.

All mighty GP, we bow before you!!!

The GP3700 is now the battery du jour

And a very good one I might add.

When the GP3300 entered the RC car scene, the Gold Peak company was regarded a minor contender when compared with the powerful Sanyo and the respectable Panasonic.

However, Sanyo had messed things big time with their Sanyo 3000 and the much better Sanyo 3000HV. The first ones were excellent as paper weights but the HV could be cared enough to last one year without becoming pure garbage.

The GP3300 appeared and Sanyo was suddenly left behind in the capacity war. Soon these new batteries were acclaimed by racers as the best performing batteries ever. On top of that the price and durability was second to none. Voltages in the region of 1.19 at 30 amps were now a common sight.

Then Sanyo launched their 3300HV. Total crap!!!! Incapable of keeping up with the GP's, even the lower spec ones they soon disappeared from the landscape. And then Sanyo puts out the new Sanyo 3600.

With an outrageous price, they were again in front of the capacity war. But... the average GP3300 had more runtime, punch and better durability. The Sanyo 3600 soon accompanied the 3300HV to the grave.

GP is now at the top of the battery war. New contenders are on the market. Intellect and LRP/NOSRAM with their VTEC (it seems to be a rebranded Intellect) at a very competitive price and with a very similar performance.

But the racers swear by GP and it seems irreversible. GP is the preferred battery.

The GP3700 is the current version and matchers like Orion, Peak, Promatch Fusion Batteries etc etc, are getting incredible numbers out of them. Who would thing 3 years ago that a 1.197 battery could be in the hands of a mere mortal? (I mean, us, the guys that race with money from their own pockets)

A few more gadgets...

There's a lot of clutter surrounding batteries and the way they should be properly charged, discharged and stored.

You'll hear the most amazing things regarding these topics. Some of them are just plain idiotic, some are weird but work and the rest is plain common sense.

One thing is sure... Heat destroys them. The other thing is sure too - They false peak at low temperatures.

That's why you can buy battery heaters and battery coolers LOL

The heater is a small device that makes you batteries reach a temperature where false peaks wont happen (in the winter) .

The double fans are used to charge the batteries and keep them below a safety temperature in hot days.

The nice thing about these two devices is the facto that they can be controlled by one charger. The Much More Cell Master... A very neat little charger loaded with all the adjustments you may want and a few more that you don't even knew that existed.

The charger I'm talking about is a product from a recently created company but already very reputed on the electric market.
Much More is very innovative and the value for money of their products is one of the best in the business.

They were very clever in signing several top drivers and sponsoring major events. I have several of their products and I swear by them. Good Stuff!!

The other device that was launched very recently is the heatsink for 6 cell packs.

When discharging or charging our packs this device will help the temperature down by acting as a heat sink. Made in aluminum it will "pull" heat out of the cell and due to the exposed air surface it will dissipate the heat much faster.

Again, this is the type of thing that most of us won't buy or won't feel a difference, but id you test it you'll see that what it does is true. In fact the cells can be several º lower in temp when charging or discharging.

Related Information

Orion
Promatch
Fusion Batteries
SMC