Power up issue when using Li-ion battery - DC1836-A (LTC2955)

Question

Hello, 
 I have the demo circuit 1836A with the LTC2955 on board, using default jumper settings out of the box. 
 If I power through VIN with a bench supply, everything works fine, no problems. 
 If I connect a Li-ion battery to VIN the device does not always power up correctly... often the LEDS just flicker and stay off, with no output on LDO. 
 Link to battery being used (ANSMANN 4S1P): 
 mister-battery.be/.../1194-pack-li-ion-18650-148v-26ah-m4a-r4-un-2447-3032-01.html 
 Battery voltage is 16.5 V so almost fully charged. 
 I can get the demo board to power up and run from the battery, but only after many attempts. Is there something I should be aware of in general when using Li-ion packs? 
 Kind Regards, 
 Anthony

ARad · Accepted Answer

I tried powering DC1836A-A from my batteries and I could not replicate the problem you are seeing. My battery packs make around 18VDC. Hot-plugging an input supply can cause voltage overshoot that can cause electrical stress-type damage, but I am not sure why hot-plugging would cause intermittent operation.)

AWM1882 · Answer

The issue is related to the BMS of the battery pack I am using, I managed to reduce the voltage transient using electrolytic capacitors, but then the issue of inrush current also causes the BMS to cut off the battery from the load. 
 So, I need to do further design work to also limit the inrush current and prevent the BMS from "tripping".... but that is a different issue, not related to the eval board :-)

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Power up issue when using Li-ion battery - DC1836-A (LTC2955)