A battery warning

[chesters1]

Not just 18650 i bought a charger from lidl and i could smell 'hot' i touched the AA nihms in it and they were almost to hot to handle ,i grabbed the lot and put it in the garden ,the plastic wrap on the batteries had melted .

The charger was replaced but i dont use it i use smart ones with overcharge overheat protection now .

Its nice to know just how real the stated capacity is ,two batches from the same place only got to half the stated capacity and a refund was issued after sending them in with proof ,the batch before were fine but the term 'up to' regarding recharge cycles is misleading and none to date have kept 80% of the stated capacity over a years use .

Just bought some eneloop pro for the detector .

 

Heres an interesting site for non rechargeables i usually use duracell but i have bought some varta to see how they are

 

http://www.batteryshowdown.com/results-lo.html

 

Whilst on the subject of rechargeables on the matter of 9v ones beware ,theres 3 voltages that can be sold as 9v.... ,7.2v,8.4v and 9.6v

If you device runs on say 6v it doesnt matter but my backup detector indicates the battery is dead and switches off if anything but a 9.6v battery is in it.

Hard to find them and most are just marked 9v with no clue to their real voltage lidl for instance.they also need a charger that can charge them a timed charger will not work correctly with 9.6v batteries (nor high capacity AA or AAA) so the charger is as important as the battery

Edited October 26, 2016 by chesters1

[corydoras]

Yup. A shoddy charger is as bad as shoddy batteries.

[corydoras]

[chesters1]

Eek battery nightmare ,but 'hand etched pcb' is no big deal theres a few of mine floating in space ,when you do short run protos theres little option to hand etch.

The milling machines just cannot handle the material i used but i presume laser etching is now run of the mill since my last one in 2001

 

In the workshop we got many repairs in where the hot glue the manufacturers (big names) used to fix components in place was becoming conductive so passing stray voltages to the next component ,once the stuff was hacked away the machine returned to normal function.

With hindsight its easy to point and 'dangerous' practices ,i remember portable radios where a 110v battery was the norm !

I suspect the 'tablet' did not contain such naughty batteries when first made but a later battery pack knocked up to repair it although tabbed batteries are cheaper and safer!and i recommend a higher powered iron!

Edited October 27, 2016 by chesters1

[corydoras]

I agree that there is nothing wrong with a hand etched board per se, but that was a pretty horrible hand etched board don't you think? Why would you bother? I'm sure you could buy a little switch mode power supply module for not too many pesos?