It’s been a while since I used my Celestron Power Tank due to the weather.  With the coming week with a good weather forecast, I decided to look at my equipments and will do some quick visual observations, I noticed that I left my Celestron Power Tank to charge but unplugged.  Plugged it but nothing happened, it’s not charging anymore.  I did some search on the web and see if this kind of thing already happened to somebody and it was good because it seems that there’s a flaw on the design.  The acid based battery cannot charge when it’s totally discharged.  A lot recommended some sort of a car battery charger.  Good thing I have a battery that is for kickstarting my car. Just did a very simple same polarity connection.  After an hour, tried the power tank and it’s now the lights are lit.  Continued with around 48 hours of charging with the usual charger and it’s bask to normal.