Another newby in this forum!

[qq8807]

Hello, I am also a newby in this forum.

By the way, would like to ask about the battery pack.

Is there anyone here knows the procedure before opening the mechanical case of a battery pack ??

Do we have to discharge the battery first before we want to open the mechanical casing ?

Please help if anyone knows, and explain why.

Regards.

 

[Boncuk]

Battery pack

Hi qq8807,

welcome to the forum.

A fully discharged battery isn't good for anything anymore.

I suppose you want to open the battery pack of an electric tool. Those enclosures are normally very tough to open.

If you possess a 'dremel multi' you might try to cut the pack cautiously (not to leave too much damage) to replace single cells and glue the enclosure with epoxy when done.

Boncuk

 

[qq8807]

Thanks a lot.

Actually I am using a tool in my office with the help of the mechanical engineer.

Hmm, I'll consider your advice.

 

[ericgibbs]

Thanks a lot.

Actually I am using a tool in my office with the help of the mechanical engineer.

Hmm, I'll consider your advice.

hi,
Why do want to cut open the battery.?

I assume its a lead acid battery, if so, the battery liquid/gel is acid and corrosive.. take care, wear rubber gloves and goggles.

If you expose the plates to air they could get very hot, have a plastic bucket full of cold water so that you can immerse the battery plates if need be.

 

[qq8807]

Why ??

OOO... actually i wanna do some analysis to understand the protection on that battery. hmmm.... that is the reason.

 

[ericgibbs]

Why ??

OOO... actually i wanna do some analysis to understand the protection on that battery. hmmm.... that is the reason.

There is a lot of information on the web regarding batteries.

When you say protection on the battery, what do mean.

 

[qq8807]

Yes, protection of the batteries.

Instead of the protection circuit that we have to put inside the battery pack, we should also consider the protection that we locate external of the PCB.

The battery can itself be heated by certain reasons for instance may be there was overcharging activities and the protection circuit of the battery was not working, or the battery could be placed on the hot surface etc...

So, we must put extra protection on the battery itself to sense the high temperature and overcurrent if let say out protection circuit failed to protect the battery at the 1st place!

So, the concept of the physical arrangement of the protection components inside the battery that I wanna to do the analysis. haa...

 

[ericgibbs]

Yes, protection of the batteries.

Instead of the protection circuit that we have to put inside the battery pack, we should also consider the protection that we locate external of the PCB.

The battery can itself be heated by certain reasons for instance may be there was overcharging activities and the protection circuit of the battery was not working, or the battery could be placed on the hot surface etc...

So, we must put extra protection on the battery itself to sense the high temperature and overcurrent if let say out protection circuit failed to protect the battery at the 1st place!

So, the concept of the physical arrangement of the protection components inside the battery that I wanna to do the analysis. haa...

Sounds interesting.

You have not said what type of battery it is.?

Some types of battery, you must NOT open.

 

[qq8807]

hmmm.... you are right.... the type is llithium ion....

 

[ericgibbs]

hmmm.... you are right.... the type is llithium ion....

DO NOT CUT IT OPEN.!

Read this and Google: Lithium Ion battery safety.

Chemical & Engineering News: Science & Technology - Burning Batteries

 

[audioguru]

Keep water away from a lithium battery.
If a lithium battery is completely discharged then it is destroyed. The battery protection circuit will disconnect the load when the voltage of each cell drops to 3.0V.
Do not have a current that is too high on a lithium battery or it might catch on fire.
Do not overcharge a lithium battery or it will catch on fire. The charging circuit should limit the voltage of each cell to 4.20V and disconnect the charging current when the battery is fully charged.

 

[Jamjoom(EE)]

Well you don't have to worry much, cause it seems u wanna open a low voltage battery, a few volts. just make sure not to touch the positive and negative terminals.

Ahmad Jamjoom

 

[qq8807]

DO NOT CUT IT OPEN.!

Read this and Google: Lithium Ion battery safety.

Chemical & Engineering News: Science & Technology - Burning Batteries

Thanks Ericgibbs , Thanks Audioguru for your concern.

As what Audioguru mentioned, I already made few studies about the Lithium-Ion battery performance.

It definitely cannot be over discharged or over charged. The nominal voltage of the 3.7V and the maximum is about 4.2V to 4.3V depends on the brand. So, any voltage with the above ranges should be saved.

If the lithium ion is discharged to 0V, the battery could explode as well as if it is over charged. To ensure this is not happen (hopefully), the Protection Circuit must work efficiently.

If the Lithium ion is going beyond its over discharge voltage, the Lithium Ion has to be considered cannot be used anymore due to its safety precaution. At this point, don't ever charge that Lithium ion battery.

I am not good actually in this field, need some valueable advices from your side.

 

[qq8807]

Well you don't have to worry much, cause it seems u wanna open a low voltage battery, a few volts. just make sure not to touch the positive and negative terminals.

Ahmad Jamjoom

emm..actually, have to, I think, because of I am going to open the 10Ah battery (14V) Lithium Ion battery. That 4.2V battery arranged in order to get this much capacity.

 

[blueroomelectronics]

Why bother asking for advice if you have no intention on taking it?