Hi all,

Thanks for your invaluable advice/comments. The matter has now been resolved. I put it to EE that a replacement was not appropriate and I wanted a refund, which they have done via PayPal. it took too long and their comments were unhelpful but it's over.

Many thanks

Edward

Hi Dave

Good point, I don't know for sure what sort it is. Given everybodies advice I have gone back to Roberts to find out exactly what has been said and they can not find a record of a returned product from Everything Electrical but they MAY have returned it under a different name. I have asked EE for clarification.

Edward

Hi Edward
Are you sure it is a LiPo and not a LiIon battery? Domestic products such as laptops etc have used this type for years and they are not the same as LiPos.
As the battery is internal and probably unmarked your best bet is the option you have chosen by returning to the supplier. if the radio is not as advertised claim your money back.
Dave

Thanks Haverlock,
I will need to go on to my PC to open the link but thanks for this.

The bottom line is should a radio made by such a reputable company discharge so quickly?

Edward

Having thought about this a little more I am wondering if its a case of high internal resistance rather than lack of charge. The internal resistance of a Lipo increases when left fully charged ( for as little as one day). A high internal will result in a low voltage being delivered to the output even when the "off load" voltage is showing a reasonable level.

This is a weighty read but will tell you (probably) more than you need to know

http://www.batteryuniversity.com/learn/article/how_does_internal_resistance_affect_performance

No, it is built in. The radio is currently with Everything Electrical.

I agree about the charge going some place, it's a question of "is this normal?"

Is the battery removable ? if so fully charge it check its voltage then remove it and lay it somewhere safe for a week and recheck its voltage. it may be that there is a current being used by the radio even in its off state.

Charge has to be going someplace!

Hi Dave

Sorry for the delay in replying. I'm experiencing problems with the mobile app.

The battery is in a new radio, a Roberts Sports 3. it's new and has been charged properly but the charge only lasts about a week (no use of the radio during this period). I bought it from Everything Electrical who say that they have sent it to Roberts who say nothing is wrong with it.

I'm not satisfied with this response, but to be honest do wonder if I am right so any advice is appreciated.

Edward

Hi Edward
LiPos do not normally have any noticeable discharge if they have been treated correctly.
As Haverlock says they should be stored at about 3.8v per cell.
LiPos unlike other battery technology can suffer internal chemical changes that are irreversible.
Discharging to too low a voltage or charging above the upper voltage will both result in this internal change accelerating.
Temperature also plays a part and charging whilst the battery is too hot can be very dangerous.
It would help if you could post some pictures of your battery showing its type and details, plus a pic of your charger.
Has the battery casing "swelled" in any way?
Dave

When stored Lipo batteries should be discharged to app. 3.8V per cell.

http://www.uterc.org/files/LipoStorageTips.pdf

All "batteries" suffer from self discharge and will lose their charge over time. This is why even commercial batteries have a shelf life. if there is no background process ( clock etc.) it sounds like your Lipo battery has a high self discharge parameter.

Hope this explains it somewhat