NLee the Engineer says:

An improvement over NiCd cells – but you can do better for less Traditionally, most solar lights sold in the US contain rechargeable NiCd batteries. But that’s only for cost reason and not because NiCd is inherently more suitable for such applications. In fact, NiMH cell is better because:- It offers 2-3x higher capacity than NiCd cell of the same size, and- It does not contain toxic heavy metal (cadmium) like NiCd cellNiCd batteries are already banned in Europe as of 2008, yet they are still being sold and dumped into landfills in the US. It is good to see solar light manufacturers finally starting to offer NiMH replacement batteries, such as this product ()Those Moonrays NiMH cells have a capacity of 1500mAh. Although this number is much higher than that of old (600mAh), it pales in comparison to name-brand Pre-Charged NiMH cells, such as or . The eneloop AA cells have a higher capacity of 2000mAh (actually measured capacity is closer to 2100mAh), and offer longer lifespan of 1500 cycle.As of this writing, those Moonray NiMH cells are priced even higher than Sanyo eneloop cells. So it is just not a good value.Additional Notes:1. Using higher capacity battery does not automatically guarantee your solar lights will remain lit longer each night. If the charging current from solar cells is inadequate (not enough sunlight), your solar lights will not stay on throughout the night, regardless of battery capacity. But if there is sufficient sunlight, higher capacity battery can store more energy during daytime, and offer longer runtime at night.2. In winter time where daylight is much short than night time, all solar lights will perform poorly. One solution is to remove those batteries and fully recharge them in any NiMH charger, then return them back to the solar lights. The extra stored energy will be sufficient to run your solar lights for several weeks.

ihgrabmail says:

good batteries Good batteries, work fine from the first day I installed them, no problems, thanks! The lights recharge them during sunny day, you don’t have to charge them at all.