Inside Battery Lithium Pack 7,4V and Protections !

[IW2BSF]

I have "open" a battery pack , in my web site you can download the PDF of this , here:



https://rodolfo-parisio.jimdo.com/nuovi-articoli-2017/



you can try near the end of my wbe page , in the section called " DMR radio ..... "



- sorry is in italian language but you can used the google translator for english !


- is a litium battery pack of an retevis dmr radio



But i think the battery pack is similar .... inside like the KENWOOD PB-42


there are 2 lithium battery connect to a PCB that :


- Protect to overcharge (over 4,2 volt ) !


- Protect to overdischarge ( down 3,5 volt ) !


- and MOST IMPORTANT charge this 2 elements in BALANCE MODE



if the battery NOT put out any voltage is probably the INTERNAL PCB protection


is an Seiko Sii integrated circuit smd at 8 pin and 2 mosfet ...is dead , but the


battery are ok !



before you put your battery pack in the rubbisch , open and control this !!!



REMEBER that if you have problems inside the TH-F6 kenwood there are 2


smd fuse .... i indicated this fuse in another PDF article in my web site !



best 73 de IW2BSF - Rudy

 

[Rred]

Rudy-
Please remember that lithium cells can be damaged in ways that are not visible. Simply allowing them to discharge completely can trip the protective circuit, which cannot be reset, because one total discharge can cause internal battery damage, and damaged batteries are more likely to catch fire or explode.
I have worked on lithium LiOn computer packs, and lithium primary cells in other equipment, and can only say that all of them are capable of making nasty surprises and sometimes toxic fumes when you are sure they will not be a problem.
Unless you can verify the performance of a battery cell, and be certain that the protective circuit is defective, you might not want to trust them. Burns and toxic smoke that eats your nose and lungs are just not worth the price of new batteries, to me.

Google machine translation:

Rudy-
Ricorda che le celle di litio possono essere danneggiate in modi non visibili. Semplicemente permettendo loro di scaricare completamente, può spegnere il circuito di protezione, che non può essere resettato, perché una scarica totale può causare danni interni alla batteria e le batterie danneggiate sono più suscettibili di accendere o esplodere.
Ho lavorato su pacchetti informatici LiOn di litio e le celle primarie di litio in altre apparecchiature e posso solo dire che tutti sono in grado di fare sorprese sorprese e talvolta fumi tossici quando siete sicuri che non saranno un problema.
A meno che non sia possibile verificare le prestazioni di una cella di batteria e assicurarsi che il circuito di protezione sia difettoso, potrebbe non voler fidarsi di loro. Bruciature e fumo tossico che mangia il naso e i polmoni non sono semplicemente vale il prezzo delle nuove batterie, per me.

 

[cmdrwill]

Thank you to Rudy for the very informative write up on the battery management.

 

[IW2BSF]

thank to all...

rRed you shure the fumes is toxic ?

73

 

[Rred]

Depends on what you call toxic. Might not cause cancer or liver failure, but from a quick distant whiff of them, I'm fairly sure they will eat out the mucous membranes and that includes lung damage, the kind that could kill you the way that "non toxic" smoke from a wood fire can. Except, way faster. The web refernces I find all say "severe irritation to the respiratory tract" and when your windpipe and lungs well up, you stop breathing. I suppose that's not "toxic" but it still kills you.

What was that Agatha Christie mystery where the victim has been shot, stabbed, strangled, all at the same time, and the big question is exactly who killed them, from which injury?