Is my VX-1 confused?

Bit of a long post, but bear with me.

The MOT on my VX-1 is due in a few days time so I thought it would be a good idea to take my VX-1 out of the garage for a few trips to make sure everything is in working order and nothing obvious at fault.

I don't ride my VX-1 much these days, so every few weeks my routine involves switching on to check the state of charge, operating the light and indicator switches, brake levers, putting in to 'GO' mode and running on the centre stand for a few blips on the throttle. I also check/adjust tyres pressures every month or so.

About 10 days ago the battery pack was around 128V so it was time for a recharge. I haven't done a deep discharge to the red light for ages owing to not riding much. I plugged in, everything was normal, fans started up and charging commenced. I checked periodically throughout the charging session and everything was fine - stable low temperature, no error messages or warning lights. The centre display showed CC153 and towards the end I believe it was at 152 on the left display at 20°C. I left it to complete the charge until the end. At the end of the charge session, I switched on to check the voltage which was around 147V - 148V with 1 or 2 bars missing from the display on the right.

Fast forward to this evening when I decided to go for a quick local ride. I knew I wouldn't be able to get full power and range straight away as it has been sat almost dormant for some time. I switched on, checked the voltage which was 137V and a few bars on the state of charge display was now missing. After a few seconds I got the red flashing battery light. I flipped the kill switch, pulled the left brake lever and the temperature was showing 28°C although ambient air temperature was around 16°C. I kept speeds low and stopped a few times to check voltage and battery temperature. Each time I checked, the voltage was slowly getting lower but the temperature stayed the same.

I covered 6.1 miles and voltage was hovering around 130V - 131V at 28°C all the while with a red flashing battery light. I remained seated on my VX-1 with it switched on to see if anything would change. Suddenly the yellow wrench symbol started to flash at the same time as the battery light and then the temperature warning light lit up constant. All 3 lights went off at the same time a few seconds later. Then, I got the red flashing battery light on again by itself. Temperature had dropped slightly to 27°C. The flashing battery light went off after a few seconds and remained off. I rebooted and didn't get any amber or red lights at all - just the normal boot up sequence with the green side and dipped beam lights.

So... is this just lack of use combined with not doing a discharge to the red light for a long time? Or perhaps something else?

Additional info: In March 2015 I had quite a bit of work done by Emissions Free Solutions including new front and rear temperature sensors with wiring and a replacement charger due to a thermal incident with one of the original temperature sensors.

My VX-1 is a late 2007 build, still on the original Ni-MH battery pack and registered new in September 2008. A sticker on the outer battery casing states it was part of the initial battery recall and was manually conditioned in March 2008. Mileage currently stands at 16,194 miles.