I'm a student who majors Chemical Engineering. I just have a question shown as below. First of all, I don't understand the answers of both 1) and 2). In my opinion, the answers should be switched.

Since the passage says that positive active materials are 'fully reduced'(R) and negative active materials are 'fully oxidized'(O), that is, a battery is fully discharged, I conclude that a battery will be charged later. Therefore, for the first charge, 150mAh * (1-0.1)=135mAh would be an answer for the first question. Likewise, after charge, a battery will be discharged again, which is the subsequent discharge. In this process, 10% of R still remains because of 10% loss of original capacity when charging, and 90% of O will be 100% converted(I'm not really sure of that because the passage just says that R->0 process gets 10% loss) so that 150mAh would be the discharge capacity. Is there anything I miss?

enter image description here

  • 2
    $\begingroup$ Please consider transferring the image to an actual text so that it is available for the search engines. Please edit your question with a meaningful title. $\endgroup$ – Martin - マーチン Feb 14 at 10:05
  • $\begingroup$ Sorry ! The equation 135 x = 300(1 - x) may exist. But its solution is not x = 1.1. It is x = 300/435 = 0.689 $\endgroup$ – Maurice Feb 14 at 11:11

Browse other questions tagged or ask your own question.