USB cable failure for cache batteries?

[journeyman]

Hello everyone. I've been using a rugged zendure battery for charging gps, headtorch etc. The battery itself charges off an sp dynamo via a cycle 2 charge - (as recommended by the community!) Whilst I'm really pleased with this set up the micro usb cable that charges the battery has failed twice, including a good quality portapow non synching cable. Ive tried all different ways of storing the battery to look after the connection, but inevitably the cable stops working after approx a month of use. All other parts of the set up are fine so is this normal or am i alone with this one? Do people tape up their connection to stop any shake rattle and roll and what about taking a spare on a multi day remote adventure...? Thanks, Johnny.

[slarge]

Can you tell which end fails? I tape the gps end with duck tape as with the port cover open it is not waterproof, plus it keeps all the grit out. The other end (battery) has been ok. You could try a small smear of Vaseline to help keep the contacts corrosion free.