4 pack to a 5 pack

Now that my 815 is going to the shop. I have been looking at building a 6v battery pack. I was at my local radio shack (now called the sourse) and they had a single battery pack similar to the 4 pack that comes with the radio and reciever. $2.00 is not that bad, so I bought one and added it and with my multi metre it comes in at 6v. Has anyone else ever tried this?

Basic misconception on these battery threads. A 4 pack or a group of 4 batteries in a battery holder is called a 4.8 volt (pack), but that is not the voltage. That is just the name. NiCad, NiMh, doesn’t matter. Actual voltage is always well over 4.8. You would expect it to be about 6 volts or maybe a little more when fully charged.

Same deal with 5 batteries. Called a 6 volt. Actually 7.5 volts or more when fully charged.

You can find sites on the internet that will tell you all about how much voltage you should expect and it is not 1.2 volts per battery. It is way way more than that. 1.2 volts in a battery is just barely above a drained state.

Just for info: I made myself an emergency 5 pack for loose batteries. I took a plastic Radio Shack holder that holds 8 batteries and put only 5 batteries in it. It is a plastic box/battery holder that takes 4 batteries sitting next to each other and then 4 more “below that row” sitting next to each other. So the size if the holder is about an inch high by about 3 inches (across the batteries) by the 3 inch or so length of the AA batteries.

I take the positve power thru the snap/red wire on the snap. So it has 4 batteries on the top row and one more in the lower area. The one lower batter has its positive feeding the red snap wire. The negative/black wire is looped and soldered to the “hole” in the opposite corner from the red snap. This is in the “level” of the single battery.

You can use a meter to see that this works - that this does make a circuit. This is very handy, tho I never do use it. It is nice to know I have it. It contains Everready NiMh AA batteries. It looks funny with the black snap wire wire just sitting there doing nothing but that is how I did it. (I’ll bet an RMG in a blow might be unhappy with that tiny red snap wire, but it might be okay.)

Sorry so wordy.

BTW, they’re called “cells” and not batteries. A battery is a group of cells, hence the term battery ‘pack.’ Just like your car battery that has 6 2-volt cells (for a 12 volt battery.)

Having experience with fast electcric power boats, I can tell you that after charging a healthy 6-cell pack, it is over the 7.2 volts that most people think. You get almost 1.5 volts on a fully-charged battery pack, and the 1.2 volts is the average voltage, with about 1.5V at fully-charged state and 0.9 volts at the discharged state. That way, you get an extra boost of voltage for the first lap of a race, then you settle iinto the main bulk of the power capacity.

When measuring the voltage of a battery pack with the usual multimeter, it is necessary to use some kind of a load, like a small flashlight bulb, or better yet, a loaded voltagetester. You can get ones that are loaded and even have an expanded scale to better see the voltage level, and it has scales for both your 4 or 5 cell receiver pack, and the 8 cell transmitter pack ( assuming they a conventional rechargeables.)

Scott-

You might be able to just get a 5-cell holder through one of the electronics supply companies like Mouser…

thx

Thank you Tomo,
To be honest I do not care if they are cells, batteries or any other name someone might call them, you knew what I ment. I you read my post I have already bought a single and added it to my 4 pack. I was asking if anyone else has tried this.

That is basically how I make some 5-cell packs. I first make a 4-cell flat pack, then glue the 5th cell on top of that and solder on the last wires.