home battery pack homemade cordless drill battery charger - sooperarticles.com
In this article you will find step-by-Step instructions on how to build a battery charger from wood chips that will allow you to work for NiCd (ni \'-Cordless electric drill battery.** WARNING ** using this method can only charge a NiCd (nickel-cadmium) battery.The type of package is usually written on it.Many newer bits use other types of batteries (Li-Ion, NiMh), it will explode if you use this program.Please do not try this construct if you are not sure.In addition, the calculation of incorrect structure or component values may cause the battery to catch fire or explode.First measure the thickness of the bar on the battery pack and tear the two blocks into the same thickness.Then, a V-groove is made to accept the circular part of the battery pack.Make a second piece with a groove to accept any keyway boss (rib) that the manufacturer may add to the package ).I found it easy to press the wood with force on the battery pack and use dents as a guide to put the slots together with my table saw.The two blocks can then be kept in place and tracked on a thin wooden head that will be on the side.Twist the sides to both blocks and test if they are appropriate.Cut the second side from a thin piece of wood.The thinner the better.It will bend when the battery pack is inserted.Cut relief or leave two screws so that the wood will bend a bit when the contacts slide in.No puzzle shape is required, but it will be easier to cut on the band saw.It does allow materials that come out from both sides, which bend when the package is inserted.A pair of copper contacts are required for the battery stand.I used #10 solid copper wire from a type NM cable that is usually used for residential wiring.Mark a pair of holes at the top and bottom edges of the battery contacts for positive, negative battery terminals.Next, peel off all the insulation from the wires.Then I bend it to U shape so U is inside the bracket and the wire is sticking out.Insert it into a pair of holes.The wire should touch the terminals on the battery.A volt-The meter can be used to check if this is working properly.The battery seat should hold the battery pack rod.Contacts should contact the two terminals of the battery pack.My bag is tapered so the end of the block is not square.I cleaned the end when I finished the table saw.A diode, an LED and several resistors are required to ensure the battery pack is charged at a safe speed.If you have any questions about how to do this, please consult an expert or exit.An error when selecting a component causes a fire.This can burn your house and maybe trigger a chain reaction that will burn your entire town.The battery pack will accept excess charging current while keeping it cool until it is fully charged-At this point they will start to overheat and may catch fire or explode.I used an AC output component, so the output of the charger is actually half of the DC wall transformer.My goal is a good, slow 1/16 C charging rate (capacity divided by 16 ).Since mine is the AC output transformer, I have to double it to 1/8.Use 1/16 in the math of the DC charger, otherwise it will kill your bag or set your house on fire.1.6Amp hour capacity/8 = 0.2A charge rate.The nominal voltage of the fully charged NiCd battery is 1.2V.So 12 v I need 10 batteries for my bag.(12V/1.2 = 10 cells).The complete discharge voltage of the NiCd battery is 0.8V.10 cells * 0.8 v = 8 v per unit.20V charger -8 v battery = 12 v difference.12V/0.2A charging rate = 60 ohms.12V * 0.2A = 2.4 watts of heat will be generated.2.4 w/2 (because of AC transformer) = 1.6Watts.I used a set of 6 resistors to approach my 60 ohms.This gave me about 3.Power consumption of 0 Watts is 0.5W resistors--Because I use the AC charger 3.The capacity of 0 w is enough, because the resistance will stop working during the negative ac half cycle.They really only reach 1.6 watts.For the DC 20 v charger, the desired charging rate will reach 1/16 = 0.1A and 120 ohms.12V * 0.1A = 1.2W.The resistance of six 1/2 Watts may also be OK, but the value will be different (120 ohms instead of 60 ohms ).Be sure to do your own calculations--Mine is just an example that could burn your house.Charging indicates that the LED should be around 0.02A max.(12V-1.7 V led forward voltage drop) = 10.3V.10.3V/0.02A = 515 Ohms.A resistance of 680 ohms is fine.This limits the current in the LED to prevent it from dying.Make a cover plate to cover the electronic equipment.Cut the wood to the same size as the side of the battery stand.Pass the wire on the wall transformer through it to complete the construction of the circuit.Make a knot on the wire to prevent it from pulling the circuit part while using it.Put the battery into the bracket, power the circuit, and test whether the LED should be lit.Take this opportunity to mark a hole for the LED on another thin wood covering the circuit.