I'll try Amorn in Big C, but if they don't have one...

Advice in Chalong may have one or able to order one. I buy the generic versions at Amorn (for APC 650 though).

Keehin on bypass have them.

Advice in Chalong may have one or able to order one. I buy the generic versions at Amorn (for APC 650 though).

Thanks - I'll give Advice a try if no luck at Amorn.

The battery in the Back-UPS 500 is "not user-replaceable", which means it was a real pain get it out. It is about 6 years old so I wasn't too worried about ripping the warranty sticker.

Keehin on bypass have them.

Thanks - I'll venture north of Tesco if all else fails.

A motorbike battery will work, but they aren't designed for deep discharge and so the plates can degrade faster than a battery designed for a UPS, not a problem unless you regularly drain the batteries completely though.

Best bet is a bettery designed for a jet-ski or the like. They are pricey but you'll see improvement in the time that the unit can power your devices if you calibrate properly after installing.

There is an excellent open-source bit of software that allows you to see and control all sorts of aspects of an APC UPS. I have only used the Mac variant and one built from source code for Linux so I can't say the the Windows version is as good, but it probably is.

http://www.apcupsd.com/

I'm pretty sure HomePro in Chalong have them, too.

I'm pretty sure HomePro in Chalong have them, too.

I seriously doubt it. I have replaced my UPS batteries on a number of units over the years. tried all the places mentioned here. Only place with stock - Keehin

Again, the generic ones are at Big C. Down the escalators, turn right, and it is the shop with the printers and tons of accessories on the RIGHT wall next to the parking lot. 700 baht.

Thanks, all. I'll post back when I find one.

Again, the generic ones are at Big C. Down the escalators, turn right, and it is the shop with the printers and tons of accessories on the RIGHT wall next to the parking lot. 700 baht.

You mean "Future Accessories"?

Don't know their name. I get my APC (generic) type batteries there all the time.

Don't know their name. I get my APC (generic) type batteries there all the time.

This place?

https://www.facebook.com/futureaccessories/photos/a.577934372300668.1073741825.571873849573387/725038950923542/?type=1&theater

Yeah, that place. They have generic batteries there.