comments:
Leaving them in your controller is discharging them which creates hydrogen gas. The gas does not recombine in alkaline batteries like it does in NiMH. They will keep rupturing. Either take them out when it's just sitting or ditch them for NiMH or another rechargeable. 1.2v will work just fine, but you may get a premature low battery warning being set off by a sensor looking for a different discharge rate and voltage drop present in a dying alkaline. If you go lithium, double check your choice is 1.5v and not 3.7v Also 1.5v lithium rechargeables often list mWh, not mAh like all the other rechargeables. You need to convert it if you wan't to know that. 1.5v lithium rechargeables can’t be safely charged in many standard NiMH chargers. You can get a charger that can handle NiMh and lithium from Xtar for around $15 so you don't have to worry if it's going to cook. Or buy a bundled charger that says it does 1.2v NiMH / 1.5v Li-on. USB-C AA versions are an option too. https://www.amazon.com/XTAR-L4-Pro-Independent-Rechargeable/dp/B0F4Q8TFZ6/