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https://liionwholesale.com/collections/batteries/products/1s1p-3-6v-3-7v-3500mah-10a-18650-battery-with-wire-leads-mj1?variant=41760969752645 //bigger longer than the nitecore but much better capacity. also LEADS!!
microcontrollers
built in imu:https://www.digikey.com.mx/en/products/detail/seeed-technology-co-ltd/102010469/16652896 ****selecting this, the power consumption is negligible enough and the imu is acceptable and it will be easy.
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