thanks for the pointers. Yuasa do seem to have the right ones... i think it needs 2 in each ups. The battery shop told me:
looking at the spec sheet it looks like the batteries are NP7-12 or NP7-12L this are both available on our web site NP7-12 Yuasa 12v 7Ah Lead Acid Battery or NP7-12L Yuasa 12v 7Ah Lead Acid Battery
the batteries are both the same size thay just have differant size terminals.
Please check sizes before ordering.
Also it sounds like the batteries are being over charged.
Thanks
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