Purpose: sequential connection of 6 18650 batteries. 2 modes of work. - 24 V Load to batteries: All batteries are getting in sequential circuit when connect signal is on (5V). - Charging: Connect signal is off. Charging Voltage 5-8 V is applied on P5. [TP4056][1] is used to charge/control the battery. On separate board LED will be used to show CHRG and STDBY status. [LTC4412][2] is used to connect 18-24 V output to load or another battery pack as following: ![enter image description here][3] Here is module sample for LTC4412 connection: ![enter image description here][4] [Mosfet][5] [1]: https://dlnmh9ip6v2uc.cloudfront.net/datasheets/Prototyping/TP4056.pdf [2]: http://cds.linear.com/docs/en/datasheet/4412fb.pdf [3]: /editor/20180206/5a79352b49baa.png [4]: /editor/20180206/5a7955db33921.png [5]: https://www.mouser.com/ds/2/308/FQP30N06L-1120205.pdf