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I have to power a circuit subject to constant vibrations (10-15 Hz with an amplitude of ca 10 millimiters) with a battery and I was thinking of a Lithium Thionyl Chloride Battery. The circuit has to be attached under a vibrating table.

The circuit is made of an accelerometer and a gyroscope (MPU6050) with a bluetooth module (HC-06) all smd-soldered, and the battery.

The circuit is going to sample and send data I get from an accelerometer and a gyroscope to an Arduino through a Bluetooth connection (once every hour, then I enter in power-saving mode and switch off the sensors).

I found many batteries online around 7,5 Ah that could theoretically power my circuit for 38 years (My max current consumption would be 30-40 mA only when pairing to the Arduino; in normal circumstances the power consumption should be around 8 mA)

Are they safe in my vibrating environment? I am going to pot the circuit, so also the battery will be potted with the rest of the circuit. Is it going to have problems with that?

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  • \$\begingroup\$ Yay, what environment is that exactly? I think you have to worry about more than the batteries to get vibration safe. \$\endgroup\$ – PlasmaHH Jan 12 '16 at 15:50
  • \$\begingroup\$ I added an information to the post. The environment is a vibrating table. The circuitry is attached to the table. So what are exactly the elements I should be careful about? \$\endgroup\$ – ThreeState Jan 12 '16 at 15:58
  • \$\begingroup\$ I am not an expert for hostile environments and it might be that potting is just enough in your case; just be careful that depending on what you use for it, some components may not like it (I have seen electrolytics dissolve with certain potting compounds, I have also seen them violently exploding after being potted). Just keep in mind that the average component is not specifically designed for these environments and potting and research carefully if you have some sensitive part (I have no idea what parts you have so can't tell more). \$\endgroup\$ – PlasmaHH Jan 12 '16 at 16:04
  • \$\begingroup\$ Is the vibration test to a particular standard? These tests vary depending on application and can cause interesting things to happen to PCBs, can impact solder joint reliability and wire terminations amongst other things. If your battery is in an enclosure (within the potting material), will the vibration cause chafing of the case or interconnect? These are just a few considerations in harsh environment settings, and can determine just what potting compound is appropriate. \$\endgroup\$ – Peter Smith Jan 12 '16 at 16:08
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    \$\begingroup\$ You might consider 'energy harvesting' with a fixed magnet and a coil in your circuit. \$\endgroup\$ – Wouter van Ooijen Jan 12 '16 at 16:24
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Firstly - you will experience more parasitic discharge or self discharge of the batteries that you expect. Secondly - The batteries themselves are a chemical reaction,and additional kinetic energy will induce some frictional heat in the battery itself. This induced heat will need to be shed to prevent it affecting the battery environment and creating accelerated aging, or worse still an accelerative heating loop (increase in temp = increase in electrical output = increase in temp) called thermal runaway. Thirdly - the battery construction will be an issue. These batteries typically use stacked coin cell type construction with a manganese dioxide cathode and metal grid collector. Movement of the cathod agaisnt the grid will cause cathode degredation and harm performance. Whether this can actually occur becuase of the vibration - I don't know.

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