Once charged, the external battery has held about 4 a week. I can not see that he would be quickly discharged when not in use so. Especially easily in a purse, he is not, but a certain weight you have probably in accordance with the required capacity to accept.
The included pouch do not like personally. The battery itself is nice but simple.
Perfect to go to be able to load the phone, and when traveling. Especially handy also, that the phone also for example, simply can load into your pocket when you walk around, etc., so you do not stuck next to power outlets.