I have played with the graphing of various batteries from HKJ's site. I have found nothing that is better than the LG 18650 E1, D1 is close. The both have the same voltage performance across discharge. The D1 has a bit less capacity (3000mah vs 3200mah).
The major difference in performance is keeping the output voltage up way further into the discharge. Hence, more delivered energy. Yes they are 4.35 charging voltage. No problem.
But I feel better having protected cells. I am going to use them in a TK75 with two extensions.
It looks like the KeepPower P1832K is an LG18650 E1 and the P1830K is the D1. Just from the mah and charge voltage (4.35V). They also appear to have the 4.2V versions as other part numbers. I have used the comparison graphs and they seemed to verify that. Then I looked at individual tests and they are clearly the cells I am looking for. But there were no part numbers in the test page.
If anyone cares to look around at curves, the E1 D1 cells are very obvious just looking at the voltage till discharge.
Looking at the various curves, the protection takes a noticeable portion of the advantage of the cells. It can be seen from the curves. There is a fairly uniform constant differential in the curves between the protected and unprotected. Presuming that the protection electronics has the same voltage drop across KeepPower's product, there is still a net advantage.
This also brings me back to the issue of protected/non-protected. As noted in my original post, I am going to stack multiple cells in the TK75. In perusing (a lot) the various threads, the results range from "no problem, I been using unprotected cells since 1950 and nothing has caught fire" to "civilization as we know it will end if you use unprotected cells in this application: and you will blow your hand off and/or burn down your house". Obviously there is a bit of a range there. In another post I said the TK75 had battery protection. A responder said no. I read the manual. It appears that the light does some form of battery protection. But remember; an expert I am not.
I don't particularly want to do something stupid. That usually leads to bad results. Most suppliers of the cell I have found do unprotected only. Much easier to get some to sell, so that is not a measure of rational. But a whole lot cheaper.
Can some of you guys provide some explainable risk values for non-protected in this light?
and nothing has caught fire" to "civilization as we know it will end if you use unprotected cells in this application: and you will blow your hand off and/or burn down your house". Obviously there is a bit of a range there. In another post I said the TK75 had battery protection. A responder said no. I read the manual. It appears that the light does some form of battery protection. But remember; an expert I am not.