Topic: Running 9v (wally world) lithium ion batteries in series... (questions)...

[taper420]

I have a set of 6 DVD 9v wallyworld batteries that are still in quite good health. I use them primarily to power my HD-P2 and V3. Just to feel safe, I always run them in parallel... two for each unit... I have a parallel cord that came with the HD-P2, and I made one for the V3. So I know it's possible to double the amps like this safely. But as far as doubling the voltage with a simple series wiring, I'm not sure how safe this is to do with the lithiums. Sure, it works fine with SLA's, but this is a different beast.

Recently I tried powering a MOTU ultralite off of one of the 9v (not in series or parallel), and even though it says it can operate between 9-18v, it had issues. It turns on, but then theres crazy noise on all the inputs, and if I switch the phantom on, it shuts off. Unless I start it running on the firewire port, and then disconnect.. then it seems to work fine.

So what do you think... wiring up a series cable to draw on 2 9v lithiums, for a total of 18v? Just as safe as the same thing done in parallel?

[it-goes-to-eleven]

I would be surprised if it works.

My 9v wallies have a built-in voltage regulator that maintains 9v as the batteries discharge.  You wouldn't be connecting cells, you'd be connecting regulators.  And in the case of the 9v version, I believe it is a booster.

The MOTU problem sounds odd.  What is the power consumption?  Maybe it draws too much current?

[mblindsey]

Wondering if you actually tried this?