Originally posted by que es tu It has higher mAh (1100 to 1050 for Pentax), 8.1 wh to 7.8wh for Pentax, and both Pentax and Jupio are 7.4v. Would these differing #s help battery life or burn out the electronics??
Some battery specs and math:
The voltage is what counts, and even that varies rather a fair amount over the course of charging/discharging a battery. A fully-charged one of these batteries (assuming it is in good shape) measures around 8.3-8.4 Volts. At end of useful service on a charge, the voltage is down to bit below 7.0 V . Here's some more discussion on this:
Some Pentax D-LI90 Battery Charge/Discharge Measurements - PentaxForums.com showing how the voltage varies during a charge or discharge cycle.
mAh (milli-ampere-hours) and wh (watt hours) are (supposed to be) indicators of how much energy the battery can store, or more usefully, how long it might power your camera. The camera will use the stored energy at whatever rate it needs, by drawing current (measured in milli-Amperes), depending on what it is doing. Suppose, the camera uses a steady 100 mA. Then, in theory, an 1100 mAh battery should run the camera for 11 hours: 100 mA * 11 hours = 1100 mAh .
Watt-hours are an alternate indication of stored energy. In terms of electrical units, a watt is equal to a current of an ampere flowing due to a potential of a volt. So, if our battery is operating at a voltage of 7.4 volts while supplying a current of 100 mA, it is putting out power at a rate of 100mA * 7.4 volts = 0.74 Watts. If, as calculated above, it can do this for 11 hours, then the total energy it can supply, in units of wh, is 0.74 Watts * 11 hours = 8.14 Watt-hours (wh), or essentially the same as the 8.1 wh quoted for your Jupio battery.
Bottom line: any battery that can supply power at around 7.4 volts will be fine with your camera. The mAh or wh just tell you how long it might be able to do it. And, as noted by several folks above, some batteries do better at meeting their mAh specs than others. I tend to concur that genuine Pentax batteries are among the best (and also the most expensive!!).
---------- Post added 12-27-20 at 04:23 PM ----------
Originally posted by tvdtvdtvd Has anyone actually measured the output of these third party batteries?
Send me one/some, and I'll give them the treatment referred to above.
Then, I can send them back.