Battery Switching, parallel then series, 150V stack -- MOSFET's?

[Jon.boston]

I'm looking for the best circuit to switch batteries from a parallel
arrangemnt to a series arrangement for stacking the voltage.

There are some high voltage (200V) and high current MOSFETs. Is this
the right approach? I'm looking for the series stack to be at
about 150V shen connected and 12V for each battery.

Can I switch both ends of the battery in and out of the circuit. I
would want to drive the MOSFET switches from a logic voltage, 5V =
Series, 0V= disconnected. Another set of FET switches would bring the
charge voltage over to the batteries.

Any pointers as to the best way to switch these batteries into the
stack and handle the large voltages would be appreciated.

I'm confused on how to drive the gates as they will each be 12V higher
than the next one.

Jon

 

[Frithiof Andreas Jensen]

I'm looking for the best circuit to switch batteries from a parallel
arrangemnt to a series arrangement for stacking the voltage.

'best' - under what constraints?

Any pointers as to the best way to switch these batteries into the
stack and handle the large voltages would be appreciated.

There can be no best way when you do not specify:

1) What you are trying to achieve, i.e. connecting 10 batteries in series is
necessary because ....?
2) What current are we talking about,
3) What kind of batteries,
4) How often you want to switch
5) How fast

Note that 2-5 could be guessed from the intended application, thus saving
work.

I'm confused on how to drive the gates as they will each be 12V higher
than the next one.

Pulse transformers, optocouplers, relays, optic fibers will all work.

 

[Tam/WB2TT]

I'm looking for the best circuit to switch batteries from a parallel
arrangemnt to a series arrangement for stacking the voltage.

There are some high voltage (200V) and high current MOSFETs. Is this
the right approach? I'm looking for the series stack to be at
about 150V shen connected and 12V for each battery.

Can I switch both ends of the battery in and out of the circuit. I
would want to drive the MOSFET switches from a logic voltage, 5V =
Series, 0V= disconnected. Another set of FET switches would bring the
charge voltage over to the batteries.

Any pointers as to the best way to switch these batteries into the
stack and handle the large voltages would be appreciated.

I'm confused on how to drive the gates as they will each be 12V higher
than the next one.

Jon

You could set up a diode matrix, and for N batteries, N-1 NPN or NFET
transistors. Nice thing is that all transistors connect to ground.

Tam