This has not been my experience as a consumer trying to buy 18650 batteries for my 3.3V ESP-8266 projects. Is there a good place to buy these? Searching Amazon for them shows me tons of AA and AAA batteries but no actual 18650's. In the past couple years, the price has gone up for me and the availability down.
Are there better options? I've read about 26650's but I have never tried them. Do they last longer? Are they safer? Can I charge them in my NiteCore charger that works great for 18650's?
How can a consumer/tinkerer wanting to scale up production take advantage of these options? The prices may have gone down at Tesla scale, but not at consumer scale.
What are you typing into amazon to only find AA? If I type "18650" into amazon I get multiple options for manufacturer, chemistry, and capacity.
As well, there are a handful of websites that specialize in selling battery cells, do a web search for "18650 for sale"
26650 cells have higher capacity and max current numbers than 18650s on average but your 18650 charger likely won't have prongs long enough to reach the pads.
If they were long enough, it would charge just fine.
Do not buy 18650 or other lithium batteries on Amazon. There are many poorly made and outright counterfeit batteries. Amazon banned their sale but 3rd parties selling them keep popping up.
Right now you can authentic 18650 Samsung cells for around $260/kWh, or 21700 Samsung cells for $165/kWh. Those are sale prices, but if you're careful and watch for deals, you can find them.
Are there better options? I've read about 26650's but I have never tried them. Do they last longer? Are they safer? Can I charge them in my NiteCore charger that works great for 18650's?
How can a consumer/tinkerer wanting to scale up production take advantage of these options? The prices may have gone down at Tesla scale, but not at consumer scale.