i have an electronic scale that includes a backup battery when 220V is not available, it needs to be powered with 6V, the problem is that the Lead Acid battery that was included is completely dry. I was wondering if i can use 2 rechargable 3V batteries that i got from cellphones in series. Will include photos if necessary.

 

The two battery chemistry are very different. You will need a different charge monitor circuit for charging batteries used in cell phones.

 

The two battery chemistry are very different. You will need a different charge monitor circuit for charging batteries used in cell phones.

All right, thanks man.

 

Plus, to help you find a replacement, the current available from a SLA is much greater than that from cell phone batteries. Besides the voltage, the available current needs to be considered as well. If that is mismatched, your operating time while in backup mode could be much less than the original battery. If the mismatch is extreme, the device may not even work.

 

Either replace it like for like, or use 6V nicads /ni-mhi as a backup...

 

The two battery chemistry are very different. You will need a different charge monitor circuit for charging batteries used in cell phones.

Just one more question, i can still charge a Lead Acid battery but with less capacity, right? Same voltage. Only one battery.

 

Plus, to help you find a replacement, the current available from a SLA is much greater than that from cell phone batteries. Besides the voltage, the available current needs to be considered as well. If that is mismatched, your operating time while in backup mode could be much less than the original battery. If the mismatch is extreme, the device may not even work.

I dont know how much current the circuit draws, since i dont have an DC ampmeter with me right now. But the original battery has a capacity of 5AH, so it seems to be designed to last a long time without mains power. Im planning on buying emergency lights so i can get the batteries, since i think those are Lead Acid too, maybe with less capacity.

 

Can you post a photo of the original battery?

 

Most emergency lights now use ni cads or ni_mhis, the larger commercial twin spots are sla batteries..

 

Can you post a photo of the original battery?

I attached the original battery, and also the new ones, that im not really sure if the new ones are Lead Acid, since they're really light-weight and very small. The batteries are 4.5 V, or maybe a little more since this are harvested from an old emergency light.
I think i have another problem now