Are all battery cells 2 Volt each.

[seanchan00]

Hi Guys,

I found 18 expensive looking wet cell batteries. They have been sitting around flat for many years yet the plates look in very good shape, only low in electrolytes. They are rather small, each cell encased in transparent plastic measuring 4.75 cm by 7.5 cm by 23.5 cm tall. Each one has 3 positive plates with 2 negative plates sandwiched between. The terminals are made of copper and the plates measures 5.4 cm by 16.5 cm with 15 cm of dark dimpled active material about 3 mm thick connected to the terminal by 1 mm thick shiny metal plate.

Question. Can I assume each cell is 2 volts? I topped up then recharged 6 cells in series with a 12 V charger and the current went in at 5 amps. After an hour fine bubbles were rising from all the cells but the total voltage remained at only 10 V. I began to worry they may be lower than 2 V each so I stopped charging. All the cells had no measurable volts before. After sitting overnight I still see 8 V. Each cell has 1.3 V now.

These batteries were originally meant for back up power supply for the power panel of a shopping complex to power the alarm and emergency supply during a fire. Each set of these imported 18 cells cost 900 USD 15 years ago.

Thanks for your help.

SeanChan.

[stephent]

They have any markings on them?----possibly ni-cads.

[badmoonryzn]

Neat I wonder if they are Edison Batteries. FerroNickel or NIFE batteries maybe? They have special needs too. Here is a site that might help you with those if they are NIFE

http://bulbcollector.com/gateway/Vintage_Literature/Catalogs_and_Brochures/Electrical_Hardware/Ediso
n-_General_Electric/1902-_Edison_Primary_Batteries_and_Battery_Fan_Outfits  

I hope this helps

[SamoaPower]

Yup, sounds like nicads. Nominal cell voltage = 1.2 volts.

[seanchan00]

If they are nicads how much AH can I expect given the no and size of the plates? The only markings are date of manufacture 083 06  02 since the complex building was completed in 1983 and below that KAP - 2K. Any advice on how best to rejuvenate them or is it not worth the trouble? I have no experience with Nicads.

Thanks for your help.

SeanChan.

[Flux]

From the volts they seem to be NiCd but the construction is nothing like I have ever seen. Normally there is no copper anywhere NiCds. I have never seen them in transparent cases.

If you have a friendly chemist try to find out what the electrolyte is, it should be KOH for NiCd's

If they are NiCd then you need to make sure the plates are covered with electrolyte, unless they have been knocked over you should just need to add distilled water. Just fully charge them and they should be ok.

I don't think you are going to have a lot capacity at that size, possibly 10AH.

You need 9 cells for 12V and the voltage characteristics are not the same as lead acid.

[seanchan00]

10 AH each cell Flux? The smell when charging is same as I smell when my lead acid battery is bubbling only stronger. I can easily test if the electrolyte is acidic or alkaline as in KOH. I will charge 10 cells in series tomorrow.

SeanChan.

[badmoonryzn]

I missed the part about 2 volts per cell, so they are lead acid. NI-CD and NI-MH are always 1.2 volts per cell.

[SamoaPower]

IF they are Nicad and IF their capacity is 10Ah as Flux guessed (good guess), then a 10 cell bank would still be just 10Ah.

The charger would need to get up to 15.5-16.0 volts to fully charge. Like Flux said, different voltage characteristics than lead acid.

Good luck Sean.

[Ungrounded Lightning Rod]

The voltage of batteries depends on their chemistry.  That's why carbon-zinc and alkaline batteries are about 1.5v, nickle-cadmium batteries are about 1.2v, lead-acid batteries are about 2v, lithiums about 3v, and so on.