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Batteries for robots or any portable advice.

pit09

I wanna know about good types,brands of rechargeable batteries, any type any voltage , about  the charger,,, etc... Also i wanna know about the battery life, how calculate. Aspects of every type of battery (Difference between any type of materials). Let your Expirience talk about them.

 

Uses:

-Robots (involves motors like Servos)

-Portables homemade Pc  (involves Rasperry pi or Beaglebone Black and LCD screen)

  • Hi Pablo,

     

     

    There is a lot of information about batteries, but let's start with the way of calculating roughly the battery life. I assume you know how to find or measure the current that your device draws (for example the RBPi-B draws 700mA and the RBPi-A draws 300mA), and your battery capacity (you buy the battery by its capacity, for example 3000mAh). Then you only have to do a simple calculation:

     

    time=capacity/current

     

    In this case, for the RBPi-B it gives 4.28 hours. This is the estimated time your device will operate with this battery. You can find different kinds of batteries (i like NiMh) and different voltages (but i assume you cant get the desired voltage).

     

    You have to make another consideration, that it isn't recomendable to drain all your battery every use, because you will shorten the life of it. So we have to change our formula to:

     

    time=(capacity*0.8)/current

     

    i use 0.8 because its recomendable to leave about the 20% of the battery before charging., and now our time is of 3.42 hours. Remember that this changes if you put more load on the battery, because it will draw more current from your battery.

     

    You can find a lot of information and buy the stuff in the element14 store.

     

    Greetings,

    Marco

  • Hi Pablo,

     

    Regarding the types of batteries there are many types available in the market.

    Each one is designed to cater some specific applications for example like:

     

    Ni-Cd : Good for high current and short time duration applications but famous of its memory effect.

     

    Li-io : Good for normal battery powered application and has been used widely.

     

    And the battery life is purely depends upon the charging cycles, how it has been discharged and the operating temperature. Allways try to stick with the limits as mentioned in its datasheet for the Discharge cut-off voltage, discharge current, charging voltage and current.

     

    And regarding the battery chargers it ranges from basic ones to the sophiscated chargers with many functions like battery health monitor, thermal cut-off  etc.

    To choose with the type of charger, it depends upon your application.

     

    Cheers.