You already have a bms? You just need a battery protection module to stop your dc/dc draining the cells below ~3v
Are your cells going in a battery holder? I notice their not tagged.
Thinking about it, that 5v usb outlet will stop working when the lvc point is reached. You could use that 5v to hold in a relay that supplies the dc/dc. When the pack gets low, it will switch off. I notice some talk in the instructions about not charging and discharging at he same time, so swapping the relay for a mosfet might not be as straight forward as you would like. The lvc board I posted before is well cheap though.
Are your cells going in a battery holder? I notice their not tagged.
Thinking about it, that 5v usb outlet will stop working when the lvc point is reached. You could use that 5v to hold in a relay that supplies the dc/dc. When the pack gets low, it will switch off. I notice some talk in the instructions about not charging and discharging at he same time, so swapping the relay for a mosfet might not be as straight forward as you would like. The lvc board I posted before is well cheap though.
I've ordered a BMS and the power bank module, my plan is that both works at the same time, connected to the batteries. Both have over discharge protection so the batteries will not get too low. The only way to charge them will be from the PB module too, so, no over charge too and correct charging method will be used.
I didn't bought a battery holder, forgot that, it's probably better than soldering connectors/tags to them, right?
I didn't bought a battery holder, forgot that, it's probably better than soldering connectors/tags to them, right?
The holder is the easy way. I used some in my other projects and found out that the batteries need to be pressed all the way to the "static" side of the holder to get contact. The holders are so tight fit that the spring connector on the other side can't push the battery enough to make contact on the other side.
Never had any problems though, but it might be possible that if the device gets an impact, the cells might move and lose contact. But in your case that only drops one cell off the group and doesn't cut the circuit.
And remember to buy single battery holders for your use... those multiple ones have usually batteries in series.
Never had any problems though, but it might be possible that if the device gets an impact, the cells might move and lose contact. But in your case that only drops one cell off the group and doesn't cut the circuit.
And remember to buy single battery holders for your use... those multiple ones have usually batteries in series.
I'll then order an holder. Need to find one that let me do the connections (to do the parallels) or find one that already does that.
Is it better with springs or "tags"?
I'm thinking of this one, what do you think?
Black Plastic Battery Storage Case Box Holder For 4X Rechargeable 18650 3.7V DIY | eBay
Is it better with springs or "tags"?
I'm thinking of this one, what do you think?
Black Plastic Battery Storage Case Box Holder For 4X Rechargeable 18650 3.7V DIY | eBay
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1S4P 18650 Holder
Lots on eBay under that heading.
If you need a specific shape pack, then you could use singles
5pcs Black Battery Storage Box Case Holder for 3.7V18650x1 Batteries Z1A6 I4P1 4894462368510 | eBay
Coil springs or bendy bits of metal, should give similar contact area.
It's interesting that Nenola's holder gripped the cell so tight around it's jacket, that the spring couldn't shove the cell along to the other contact.
Lots on eBay under that heading.
If you need a specific shape pack, then you could use singles
5pcs Black Battery Storage Box Case Holder for 3.7V18650x1 Batteries Z1A6 I4P1 4894462368510 | eBay
Coil springs or bendy bits of metal, should give similar contact area.
It's interesting that Nenola's holder gripped the cell so tight around it's jacket, that the spring couldn't shove the cell along to the other contact.
My $2 device was a fail. It worked in isolation, but with so little bass&treble that the controls on the amp I was feeding, had nothing to work with. You could turn up the bass&treble controls all you wanted, with no audible difference. Once the board came near anything, getting a connection at any distance was almost impossible. I have a radio background so tried a few things, but no. It was being very difficult.
Looks like I'm looking for friends with benefits again.
Looks like I'm looking for friends with benefits again.
lol@refund
The worst part is having to start all over again. I got a broken denon amp, fixed it, put in a 5v phone charger for supply, that was nearly 6v so in went a regulator. Only to get it all looking nice and find it sucked from every angle.
I should crowd fund some airline tickets and feed it to them. It's cheaper than the return postage lol
It's all good though. I have ordered the one that turns my yard into the burning amp after-party. Are you really still waiting though? I'm going to need to hand out umbrella's by the time everyone gets here.
The worst part is having to start all over again. I got a broken denon amp, fixed it, put in a 5v phone charger for supply, that was nearly 6v so in went a regulator. Only to get it all looking nice and find it sucked from every angle.
I should crowd fund some airline tickets and feed it to them. It's cheaper than the return postage lol
It's all good though. I have ordered the one that turns my yard into the burning amp after-party. Are you really still waiting though? I'm going to need to hand out umbrella's by the time everyone gets here.
The instant friends board did the trick. Full range audio output. No voice at power up. Just a little door bell noise for power, and another for connected. Both at a volume comparable to the music streamed from of my android device at full tilt. No need for any programming of the board, though locations for adding typical buttons are there. Volume/Mute/Track Change. That kind of thing. With it's wide voltage range (as much as 30v) it's everything I'm likely to need, for just £5
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