Review on Tenergy Charger Self Discharge Rechargeable Batteries by Alison Jackson

Didn't know anything about this brand and took a chance based on reviews. Regular NiMH 9V retail about $10 each so it's still a good deal to get 4 and a charger for about $30 including shipping and postage assuming the battery and charger are the same as worst case regular NiMH 9V or a simple timed 9V charger. .Packaging and processing of the products are first class, comparable to well-known brands such as Energizer or Duracell. The charger not only switches off when the end voltage is reached, but also has a backup timer to prevent overcharging. Out of the box the batteries charge in less than 1 hour and this has been confirmed because I did it 4 times, one for each battery. With an empty battery I had at home, it was fully charged in less than 2 hours. Doesn't feel hot. It works as described when the LED is RED while charging and turns green when charging is complete. The charger is very small and pocket-sized. Battery9V batteries consist of several cells connected in series, it can be 6,7,8, giving a final voltage of 7.5, 8.4 and 9.6 V DC. Cheaper 9Vs use 6 cells and the benefit of more cells is that devices that run on 9V batteries will often shut down when low voltage is detected. So, more cells mean the battery will last longer even at the same mAh. These cells end up at 9.7V, so you can be sure it wasn't 6 cells at 9V. I was skeptical that these batteries actually have low self-discharge. It's been about 1 month since I charged 3 tenergy batteries and a new standard 9V NiMH battery together and after that time the standard NiMH battery has self-discharged to 8V while these cells are still have 9.7V! I used one of the multimeter's Tenergy batteries and surprisingly it's still showing full readings after over a month of use. When used with a 6-cell 9V NiMH battery, registers 50% in 2 weeks.