Constrcuting 48v Battery from small 12V low capacity batteries

[romekgm]

Hi, I need some help with the electronics of my system
I have a configuration of :  Bergey 48V XL1 Wind Tubine  connected to  AC2DC Transformer that connected to Midnite Solar 250 that connected to  Battery 48V that connected to  Tristar Charge Controller(used as an electronic switch to transfer excess power from Battery to Dump Load) and than connected to a  Bunk load ,a lot of connections :-)
Now I don't really need the Battery ,my system is for education purposes only , but as I have no choice, I want to construct a cheap 48V battery from 4 12V Batteries in serial.
The cheapest batteries I found , have very low AH capacity(5AH), but as I don't need the power stored , and the TriStar controller should detect if My Batteries are over charged and transfer the power to the Dump Load , does it matter that I have a very low AH storage capability ?
Am I going to cook my system or is it safe to use it with such weak batteries? if its ok ,in theory could I connect 32 1.5 batteries is serial?
thanks in advance
Roman

[mike90045]

in the 15 seconds the turbine takes to charge the tiny batteries, they will go BOOM!  Then the charge controller will throttle back the charge rate.   
Sorry.   the best guess I can come up with, is 4, generic deep cycle batteries, about $90 each at a big box store.

[romekgm]

ok tnx, I understand 5 AH is not enough but
what is the minimum AH needed from the Battery to operate safely ?

[zoneblue]

The smallest battery that will accept a high charge current will be either LifePo4 or AGM.

AGMs (obviously not talking UPS style ones) can often take up to 0.5C. LiFePo4 can often take up to 2C.

So to work that out:

- your max out put from turbine= Imax
- Ah battery for AGM= Imax/0.5;
- Ah battery for LiFePo4= Imax/2;

Take these numbers with a grain of salt; individual batterys will have their own specs.

However, if you have a turbine and charge controllers, maybe adding a real battery will a make the system actually usable. In which case good old FLAs, GC2s or L16s etc wil likely be the path of least resistance.

[romekgm]

ok, got it, thank you