Vernier does not sell TI replacement batteries.You can purchase replacement batteries from the TI Online Store TI-Nspire CX II and TI-Nspire CX II CAS TI-Nspire......
LabPro needs 1.5 V batteries. Standard alkaline batteries will provide 1.5V. Cheaper “heavy duty” batteries will not provide 1.5V for very long, and are not......