please help with a project

[universitystudent]

hello, im in 4th year university and have some questions about a project i was assigned. my objective is to provide electricity using a NiCd cell at 2kW for 4 hours a day. The power required is 110V AC steady-state.

I have decided to use a 10 cell stack, each NiCd cell being 1.2V, giving 12V DC total. Then use a DC-AC converter to give 110V AC. Does this make sense? Do i need a transformer? I can't find a voltage-current curve anywhere to use, so i dont know what current i should run it at. I'm also not sure how to find how much heat is produced (kJ), and the total energy used (kW).

I am then asked to size the NiCd cell come up with a block diagram of how it works.

can anyone give me advice on how to design the cell? i just have to design it on paper, not actually make a cell. i'd greatly appreciate any help. thanks

 

[Hayato]

OmG, good luck!

I'm also not sure how to find how much heat is produced (kJ), and the total energy used (kW).

I'm sure you'll find the answers for those questions in your High-School Physics book!

 

[justDIY]

2000 watts of energy, for 4 hours is 8000 watts ... unless your dimension is goverened by a different set of physics from mine, there is no way you'll get 8kW out of 10 nicd batteries

a 1.2v 10a nimh d-cell is 12 watts, for one hour, provided the cell can maintain that rate of discharge ... so ten cells gives you 120 watts, a long way to go to reach 8000!

 

[hjames]

There are batteries, and then there are *batteries*. Like the following:
**broken link removed**

1500 AH. yikes.

[Oh, and there are *Batteries* that you don't want to be anywhere near when they're running:
https://saftbatteries.com/120-Techn...mtechno=Silver+systems&Intitule_Produit=DM2A1
]

 

[audioguru]

The fun is when you design a sine-wave inverter for 2kW at 120VAC.
Usually magic is used to stepup the 12V from the battery to the much higher voltage. Didn't you study about magic in your 4 years at university?

 

[justDIY]

good grief ... 210v at 480a for > 13 min ... since they're for torpedoes; my guess is non-rechargeable!

 

[audioguru]

Those new hybrid cars use hundreds of volts from many tiny AA Ni-MH cells. If they can power the car up the side of a mountain when fully loaded then surely they can run an inverter for a while.

 

[Hero999]

Use 134 AA cells then you won't need a transformer. All you need to do is build a large bridged class D amplifier to get your sine wave, or use an h-bridge an suffer a modified sinewave.