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Batteries that kill?

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  • Guest
    #1

    Batteries that kill?

    Just another strange thought. After reading the thread about testing current draw from a bettery whilst the boat is in the bath! and

    having just purchased a 4.2 amp 7.2 volt battery that can peak at 20 amps, It has occured to me that we are getting closer and closer to lethal voltage/ampage batteries.

    As anyone that has elctrical knowledge knows the relationship between voltage and amps is governed by Ohms Law. The resistance of the human body governs whether a certain voltage/amps will kill you.

    eg. 1000volts at 2ma will not kill you. but 240v at 13 amps will.

    Just wondered if anyone had heard of any r/c guys meeting their maker due to an R/c battery.
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    • wonwinglo
      • Apr 2004
      • 5410
      #2
      I hink you are right Tiger,we are getting closer to lethal power sources,I once saw the results of a short circuited Nickle Metal Hydride in the back of a salesmans car,the whole lot caught fire setting off a chain reaction with the other batteries whilst he was driving down the motorway.

      After that escapade he made sure that his battery stocks were well insulated.

      With the advances in batteries in recent years especially by NASA we could be in for some pretty high powered stuff in the not too distant future.

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        • Guest
          #3
          Barry has hit the nail on the head here.

          Don't worry about elctrocution until you're working with voltages in excess of 100volts. Short circuiting any battery will cause that battery to heat up and increase the risk of explosion and fire - hence the recent recall of some laptops due to exploding batteries.

          Scottie

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            • Guest
              #4
              Talking about shocks...

              I work in electronics. A few years back, I was working on a laser barcode scanner that uses a photomultiplier tube. In order to get the tube to work you need a lot of negative voltage. I got hit with -625v DC. It is high voltage but almost no current. Hurt like a bugger. It went in one hand and out the other. My back was sore for days.

              Bob

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                • Guest
                  #5
                  WE USE 48 VOLT NICAD PACKS AT WORK ON OUR MODEL VILLAGE TRAINS, THE CELLS ARE d SIZE AND WE BUILD THE PACKS WITH GOOD QUALITY CELLS, AND WE USE A THERMAL DEVICE INSIDE THE PACK TO MONITOR TEMPERATURES WHILST CHARGING,

                  THE BIGGEST SHOCK I HAVE EVER HAD IS WHEN ONE PACK HAD A SINGLE CELL THAT DECIDED TO INTERNALLY FAIL, THE CELL THEN EXPLODED, THE DAMAGE TO THE MODEL WAS EXTREME AND THE DEBRIS AND MESS WAS SCATTERED FOR SEVERAL FEET AROUND THE MODEL....... I CONTINUE TO HAVE NOTHING BUT RESPECT FOR ALL THINGS ELECTRICAL !!!

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                    • Guest
                      #6
                      WE USE 48 VOLT NICAD PACKS AT WORK ON OUR MODEL VILLAGE TRAINS, THE CELLS ARE d SIZE AND WE BUILD THE PACKS WITH GOOD QUALITY CELLS, AND WE USE A THERMAL DEVICE INSIDE THE PACK TO MONITOR TEMPERATURES WHILST CHARGING, THE BIGGEST SHOCK I HAVE EVER HAD IS WHEN ONE PACK HAD A SINGLE CELL THAT DECIDED TO INTERNALLY FAIL, THE CELL THEN EXPLODED, THE DAMAGE TO THE MODEL WAS EXTREME AND THE DEBRIS AND MESS WAS SCATTERED FOR SEVERAL FEET AROUND THE MODEL....... I CONTINUE TO HAVE NOTHING BUT RESPECT FOR ALL THINGS ELECTRICAL !!!
                      If you are interested in the destructive power of electricity have a look at the attached pictures.

                      They are of one of our 6.6 KV main propulsion transformers that failed one day and went bang. We never found out why.

                      Each one of those large circular objects is a primary coil weighing about 2 tons. The steel casing that encloses the transformer looked like a rugby ball shape afterwards with the force of the blast and had to be cut away.

                      In the second and third pictures you can see the laminated core has started to be removed in preparation for dismantling the coils.

                      If you look at the last one you can see one of the main coil connections which is about a 32mm brass nut on a stud has been completely vapourised in the blast and was never found.

                      [ATTACH]15190.IPB[/ATTACH]

                      [ATTACH]15191.IPB[/ATTACH]

                      [ATTACH]15192.IPB[/ATTACH]

                      [ATTACH]15193.IPB[/ATTACH]







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                        • Guest
                          #7
                          and the smell of burnt windings on am otor or a cell after destruction lasts for ages... these transformers must stink the place out after a burnout like those pictured..............

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                            • Guest
                              #8
                              We just considered ourselves lucky that no-one was near it at the time.

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                                • Guest
                                  #9
                                  yeah i can understand that..... a near miss alright, and probably a starting point for about 25 documents to be written !

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