I haven't used my drone for a few months but fully charged the battery and connected. Drone 3 standard. App said the firmware needed upgrading. Everyone was turned on, connected and working.  The app said the update had failed at 48%, drone turned off and now no matter what I do I can't get any lights to appear on the battery.  (even when plugged into the charger)

Any advice?

Hello there. We apologize for the inconvenience. You may refer to this tutorial:
or this:

Sounds like it bricked your battery.  Do you have a spare?  If so, try and update again.

I suspect leaving the battery sitting for two months has damaged the battery.

Hi. I am sorry to know about the issue that you are having with the battery of your DJI Phantom 3 Standard. The battery seems to be depleted. I would suggest purchasing a new intelligent flight battery for your DJI Phantom 3 Standard for you to be able to fly your Drone once again.

I've only used it a few times and I full charged it last night.  I can't believe the battery is now 'faulty'.  Surely the battery isn't fit for purpose if it dies so quickly.  8 thought there were laws against this sort of this where items are sold which aren't fit for purpose.  I can't recall seeing anywhere that you need to keep using the battery to stop it from die-ing. Doesn't sound like an intelligent battery to me.  A new battery is £100 + crazy!

WD9EON Posted at 2018-7-24 08:24
I suspect leaving the battery sitting for two months has damaged the battery.

A battery should not go bad sitting for two months.  Especially one designed to self discharge. And if that was the case the drones that sit  on the shelves for months before being sold would be DOA.

Also, he stated it was fully charged before starting the update.

Way too often we see updates screw up perfectly fine drones. That is why I will never update mine.

I'm in the UK and goods bought here are covered by the sales of goods act.

What is the Sale of Goods Act? The Sale of Goods Act 1979 requires goods to be as described, of satisfactory quality and fit for purpose. ... The only time goods are not required to be satisfactory quality is if a defect or issue was specifically drawn to your attention before you bought them.

Surely dji should replace the dead battery's