Hello & Welcome to Just Answer,
Sorry to hear of the battery issue with your device.
First, may I ask:
HOW LONG does the battery last IF it is allowed to FULLY charge (about 4 hours from a HIGH POWER adapter or 6 hours from a computer), and then you turn the device on?
Next, may I ask: Do you believe you have the capability of taking the case apart on this device, and installed a new battery yourself (or with the help of a friend)?
If so, batteries for these devices can usually be found online (eBay comes to mind) for a reasonable price ~ AU $20-$25.
Here is an example search I just did on eBay (click link below).
If you want to see how the battery is replaced, I have a link to a video that shows that process.
Nuvi 2455 battery replacement video.https://www.youtube.com/watch?v=PqtHzQznQLY
Please take a look and let me know if you think you (or a friend) could do that.
Thanks, ***** *****
I see it has been a few days and I just wanted to follow up to see if you have any more questions concerning this issue or if the issue was resolved.
I look forward to any further questions or results that you may have.
Thanks, ***** *****--. .-(im)