Anyone know the battery format? That is, are there enough cells to make 18.5V (5 cells) in a format that might fit in the power pack of a drill (B&D HPB18)? The HPB18 is just a touch smaller (5x2.5) so probably buying 4 or 5 banks and stacking them wouldn’t work. A 50Ah drill battery pack would be somewhat awesome. You could use it to build you off-grid house, on one charge! I’d settle for 5-10Ah.
@ergomeh They won’t be the high current cells that a tool pack would use, even if they are the right format. This pack is also too thin to have 18650’s inside. I’ll guess that it has prismatic or pouch cells of some sort.
@phr@dvermilion I rebuilt one pack with a small (2500mAh) RC pack - five prismatic pouches. I added a 15A 5S BMS (all ebay purchases). The BMS will cut out on the drill if the battery is fully charged and you pull the trigger all the way fast - current surge into the motor at startup. Otherwise, 15A seems enough, although I haven’t tried it in the circular saw which probably pulls the most current. The BMS was ~$3.50, could probably get, say, 25A for a little more. The RC pack was $25 and even though 2500mAh goes a long way, 10Ah for $10 would be much better.
@djslack Could be 2P with a small power converter to 5V but a boost makes sense. I don’t know the economics of large cell pouches, the only hope would be that small pouches are lower cost and so packing a number of small pouches makes economic sense - somehow I doubt it. I’m certainly not confident enough to blow $20 on finding out. Surely someone must have had one of these (or one of the many other Mophie morphology ) expand enough to open the case.
Also just realized that I can buy a 5Ah lithium HPB18 on ebay for about $35, so now there’s a price-point which would seem difficult to beat. (But at least the discussion wasn’t a complete waste - for me).
@djslack I have a load of the B&D 18V tools. Some bought at full price, some yard-sale/thrift-store purchases, some were just given to me. And a load of dead NiCd battery packs (nobody gives/sells tools with working batteries). The lithium upgrade makes them “better than new” and it’s simple. For rev one I just pushed a RC battery into the existing case and use an RC charger. Rev 2 has the $3.50 battery management board which means I can charge it on the original charger and it should prevent over-discharge. The NiCd circular saw was useless, but with the (non-BMS) lithium it’s now a handy tool for a couple of quick cuts - haven’t tried with the 15A BMS limit.
@djslack Under crazy lithium upgrades, I put a 20Ah marine lithium (40A max) as the 12V battery in the Prius. The lead acid was on it’s way out, and with no one driving the car during lockdown quit completely. The BMS should stop the lithium over-discharging so the car can be left undriven without concern. (For a while, I drove it with one of the Jump Starters from MorningSave).
I already have two of these, but might buy more if someone knows of a way to force them to stay “on.” If I turn off the screen on the device, it stops drawing power and the battery pack turns off and won’t charge when the battery on the device runs low(unless I manually press the power button on the battery.)
@makhay Yes 5V only except as a pass through device.
It has USB-PD, so it can “tell” the connected device that it supports any voltage between 5.0 and 5.0 volts at up to 3 amps.
My Pixel 3 phone sees that it supports USB-PD, so it says “charging rapidly” when connected. When connected to a charger that supports 9 volts or more, the phone requests 9 volts, and draws up to 2 amps, for a maximum of 18 watts. The phone maxes out at 2 amps regardless of the voltage, so it can only draw 10 watts from these.
If I plug the power brick into a 5 volt USB source, while my phone is plugged in, both my phone and the power brick will charge. If I use a source capable of delivering more than 5 volts, then the phone negotiates a higher voltage. The power brick passes the higher voltage onto the phone, but doesn’t charge itself.
My phone won’t draw more than 1.0 amps from USB source without USB-PD, even if the source is capable of much higher currents. The power brick draws as many amps as it can until the voltage droops. The output of the power brick always has USB-PD. My phone will happily draw 2 amps through the power brick.
I got to say, I’m spoiled by some I’ve bought here in the past with the USB C or Lightning cable built into it, it is less hassle to deal with as I don’t need to worry about bringing an extra USB cable to charge most devices. Then I can still use the regular USB ports as needed for extra devices or anything that doesn’t use the built in cable.
Update: I kept the batteries plugged in overnight.
One of the batteries appeared to take a charge, got all the way up to four lights lit. When I plugged my phone in, it charged my phone for ~10 minutes and is now 100% dead.
The other battery never showed any signs of life despite being plugged in for 12+ hours.
@narfcake I know lithium batteries aren’t normally shipped with a full charge, but these were 100% dead on arrival which is usually a sign they’ve been sitting in inventory for an extremely long time (and being stored completely discharged is pretty bad for lithium batteries, so not surprising these would be DOA).