3.7v battery with 3 wires

wizpic

Advanced Member level 3
Joined
May 23, 2004
Messages
792
Helped
108
Reputation
216
Reaction score
72
Trophy points
1,308
Location
London
Activity points
6,404
I have been given about 30 of these batteries as I thought I might be able to use them.
The question is what’s the white wire for monitoring or something like that ?

 

Sort by date Sort by votes
That's usually a temperature sensor, which is also indicated by the silkscreen "T". This sensor is used to ensure state of operaion (charge & discharge).

BR
--- Updated ---

... safe state of operation.
 
Last edited:

    wizpic

    Points: 2
    Helpful Answer Positive Rating
Upvote 0 Downvote
i did not see the T until I zoomed in, so I don’t really need to use it ?
Could I use the standard TP4056 charger for this battery ?
Has I would just like to have it all in one case and plug it on charge and have seen mixed reviews for the TP4056

​

 

Upvote 0 Downvote
I don't know how the TP4056 is realized and how it ensures safe charging of the cell ( datasheet link missing).

The purpose of the sensor is to monitore the temperature of the cell while charging and discharging, and to avoid it gets is too high. Have a look on thermal runaway events, which occures at a cell tempeture of ~60°C. If you use a too high charge current, this might "fire" up the cell.

Does the TP4056 supports a cell temperature measurement? If yes, which kind?

BR
 

Upvote 0 Downvote
I've had bad experiences with cheapo TP4056 modules from China, the IC itself may be good if from a reputable supplier. It monitors current to the cell via a series resistance and also has a temperature sense input from an NTC thermally bonded to the cell body.

My experience has been catastrophic failure when a fully charged cell has decided to discharge itself back through the TP4056 for some reason. As you can imagine, a post mortem after a Lion cell has dumped through a tiny IC isn't possible, even after the ashes have been cleared away.

Brian.
 

Upvote 0 Downvote
You must log in or register to reply here.

Similar threads

Menu
Log in
Register
Cookies are required to use this site. You must accept them to continue using the site. Learn more…