Thought I'd drop a note for those of you who are Panasonic CGR18650CH battery fans. Another shipment seems to have reached the US, so if you've been patiently waiting to see if any show up, they're here now. This battery has been discontinued, so if you want them,
now's probably the time.
RTDVapor has them in stock (just came in today) in all three forms. The
flat top version, the
button top version, and the
protected button top version. (There is really no need for the protected CGR18650CH; the CGR18650CH is IMR type chemistry, and really doesn't need protection for our use).
$9 each.
If you happen to want four of the flat top version CGR18650CHs, you can get them for a steal at $26 (about
$6.50 each) from the
Amazon link posted here earlier. I just received a four pack of these, and they're testing out perfectly, delivering 2250 mAh when discharged down to 3.2v, and 2300mAh when discharged down to 3.0v. (1 amp load). The
CGR chemistry is such that the drop from 3.2v to 3.0v only takes about five minutes out of the 130 minutes it takes to discharge the cell at a 1A drain. The
NCR chemistry used in the current TET cell causes the voltage to drop earlier in the discharge curve, with a more gradual decay, which is why your Cera works as well with this 2250mAh cell as it does with the new 2900mAh cell, and why it doesn't work nearly as well with the 3100mAh and 3400mAh cells. (mAh ratings alone don't tell the whole story).
And speaking of the 2900mAh NCR cell, if you're a fan of the current 2900mAh Panasonic that TET ships, but would prefer one that's protected (since the NCR cell
isn't IMR type chemistry), RTDVapor has the 2900mAh
Panasonic button top protected NCR18650 in stock too, for $12. They don't sell unprotected versions of this cell.
Tests have indicated that the
protected version of the NCR 2900mAh cell provides the same amount of power as the unprotected CGR 2250mAh cell, and the unprotected NCR 2900mAh cell provides ~10% more (mostly due to it being able to be discharged to a lower voltage since it doesn't have a protection circuit). In real world useage with a Cera, I suspect it will be impossible to tell the difference between the CGR, NCR, and protected NCR. The four pack CGR price from Amazon is pretty hard to beat (and it's Prime eligible and was delivered the next day, not a month from when I ordered it via slow boat from China).