Hi, I had the same problem with four wind sensors that stopped working after about 2-3 years. The AAA batteries installed were Topcel 1000mAh ZnMn; available from China and alibaba.com. I had a hellofatime finding info on rechargeable Alkaline batteries available in N.America: Radio Shack, Grainger, and Batteries Plus all say alkaline is not rechargeable and the NiMh ones only charge to 1.2v not 1.5v; and we all know how sticky LC is with voltages so I didn't want to experiment.
So thanks for the lead, I just ordered 8 of them from Amazon for $13, which beats the hell out of $240 to replace the wind sensors, and I'll leave the rest to history after I get them.
Somewhere on these posts I saw the word "surgical" when describing how to change the batteries. That is only true if you turn the sensor upside down (like I did, of course) when trying to get it apart. The surgical part comes when trying to relocate a bearing that falls out. Brain surgery. SO BE CAREFUL WHEN YOU FIRST OPEN THE WIND SENSOR TO REPLACE BATTERIES!
I don't know why LC doesn't try to help here by showing the 'repair' and offering replacement batteries or offering to change out batteries for you for a small percentage of entire wind sensor replacement ($60). Throwing away a good instrument for lack of batteries is not very environmental or good customer service.
Also while I'm up on my soap box. I also don't know why LC doesn't publish a numeric wind direction (that shows on the display to the nearest degree) so that can be plotted on Heavy Weather. Wundermap does take that data as it is uploaded and plotted from 0-359 degT. Most meteorologists know that wind is 'everything', showing transitions from one atmospheric state to another such as the morning transition, advection patterns, and frontal passages.