Archive for the ‘Li-ion batteries’ category

HTC says their 1730mAh Battery used in their Evo 3D Smartphone Has a Maximum Charging Voltage of 4.35V??

July 18, 2011

HTC’s Evo 3D has been having Over-Heating issues as well as Over-Charging issues according to some of Sprint’s customers. Two weeks ago, HTC said they were not aware of these problems, and were unable to duplicate them, but they would pay attention to the issue stated by some customers. Sprint said there are NO problems. HTC was a little more open-minded, although when asked what their specifications were for the battery being used regarding voltage, their answer was that the charger is 5v @ 1a, which is not really a complete answer as most usb chargers are of this spec.

The voltages being recorded by some customers were sometimes upwards of 4.35v and higher. This was very disturbing to say the least, due to the fact that the maximum charging voltage of 4.2v Li-ion batteries is 4,2v +- .05v. 4.35v for a 4.2v battery is Extremely Dangerous. Coupled with High Temperatures is a Disaster waiting to happen.

HTC just came out with their 2nd response regarding the Over-charging and Over-heating issues with the Evo 3D. They Now say that the maximum voltage of their 1730mAh batteries is 4.35v.

4.35v Li-ion batteries are not commonly used. When they are used, they are usually cylindrical, and used in Laptops or Flashlights. Why HTC failed to let their customers know about the 4.35v spec in their 1st announcement is curious to say the least. And why different customers having different cut-off voltages? Some are having 4.35v and higher, while others are having 4.2v.

I use Li-ion batteries in my flashlights which have a nominal voltage of 3.7v, and at their maximum, terminate at 4.2v. Usually they terminate prior, between 4.15-4.20v, But NEVER terminate higher than 4.2v.

I don’t have a lot of faith in HTC’s announcement regarding the 4.35v maximum voltage. If anyone has any insight into this issue, it would be much appreciated.

 

Advertisements