So it begins...... Battery spot welder

[rvpopeye]

It's good to see you found the defect in the 5.5x2.5 and even better that you could get it back to proper function !
The 6s1p powering an iron build is cool, errrr hot ! Get me home function is a great bonus !

I expect my mfg batt pack to hopefully arrive this afternoon, and more hopefully that FedEx didn't cause damage !
Might be a bit late weather wise , high today in upper 40s , MAYBE 50. The older I get , the warmer "cold" is.

Woof woof , arf arf , bark bark , Fiona's a good dog , yup yup ! Ear rub time......

[rvpopeye]

OK , just read your second post. It seems they produce new products faster than you can test 'em and elect one as best.
They are making better versions all the time . Maybe those incremental improvements will morph into a new something nobody has imagined until it's released ?
The experiments are useful as edumbification as well as some cool prototype items.
I'm waiting for you to debut the flying esk8 ! "Eskate phone home" lol tricycle not included. Well , it COULD happen .

Wow , the sun just appeared. Gotta go clean my panels ! I'm under the canopy , pine and oak that is , shedding on my watt-hours ! arrrgh .

[sternwake]

Ears scratched.

These  Voltage Boosters have been around for a few years at least. I was just avoiding re acquiring  the '1800 watt'  red one for its physical size, larger price, and what I assumed was unneeded capability.

There is a '600 watt' booster that is black with a bottom mounted heatsink that I do not own.  I should see what its max input amperage is, if listed.

  I do have the buck boost version of the black 600 watter, powering one of my 24v papst fans, but it kind of struggles on start up were my other buck boost does not.

The 12v DC nominal  input being limiting factor, was not a factor until I made the BAK 45D pack  and had cells which could be charged much faster.

Anyway the red booster opens up the potential for 10 amp, 420 watt bench charging, where the other boosters  were 150 to 170 watts maxxed out,  on 12v nominal input.  The voltage potentiometer is not super sensitive at 42v either, like my other boosters.  it is hard to not blow past the desired voltage and then difficult to dial  it in precisely on the others.

The BAK 45D as 2 parallel can handle 26.4 amps charging as least for the low to middle part of the recharge, but my BMS says 10 amps max charge,  as does my charge port. so that is the new limiting factor, not the booster.

I have used the new 1800 red booster on the bench at 170 watts and it barely got warm.  I was only discharged to ~ 80% though so 170 watts did not last very long. 

Hope your new battery arrives safe and was constructed with care from decent cells.

My electronics guru friend has a BT speaker that he loves to use, which I find surprising as he is an Audiophile, but convenience wins.

Its internal battery was just some junk 18650 and he said it would still last 6 hours when new, but that tapered to 3 recently.

He opened it up and saw there is room for 4 18650's, and if the little cradle and retaining posts are removed, 4 21700's can be made to fit.

So he ordered 4 EVE 58E, a very high capacity 21700 energy cell, 5700mah and 16.8 amp CDR.  They are being sent here to me so I can spot weld them in parallel to a 1S BMS, and this should have 10x the battery capacity than the cell which is currently inside his BT speaker.

He said her ordered a few extras for me, that i am assuming are extra EVE58E . My only 21700 device is my Armytek headlamp, and I have a pretty Good Samsung 50S (5000mah, 25amp CDR) already  in there, but at 10 amps max draw of this headlamp, the EVE 58E would probably run only a little warmer, but for ~15% longer.

I like to hang both my 90 degree headlamps from my cargo short Thigh pocket  Via their deep carry clips, on our late evening / nighttime cruises.

The JP30 cell in my Sofirn HS40 is pretty good thrower  on its own, but hanging the Armytek next to it is like the wide angle floodlight powerhouse.

[rvpopeye]

Fedex arrived a little earlier than expected .
I had just made it back from Wallys in time , now on chgr.
All sealed up in a metal case.
Haven't peeked , warranty seal in place. Waaaah , pirate sad but very happy as well !
Tomorrow new range testing begins.
Planning to swap 'em out when the second bar (out of five) goes out .

I haven't been out after dark yet but I have multiple lights that produce more light than the sun !
Ok , not that much but the panhandler that hangs out on an intersection median strip I go by keeps yelling at me to turn that fcking light out ! I have a couple red taillights that flash and one can stun small animals and possibly a panhandler..

[rvpopeye]

Fedex arrived a little earlier than expected .
I had just made it back from Wallys in time , now on chgr.
All sealed up in a metal case.
Haven't peeked , warranty seal in place. Waaaah , pirate sad but very happy as well !
Tomorrow new range testing begins.
Planning to swap 'em out when the second bar (out of five) goes out .

I haven't been out after dark yet but I have multiple lights that produce more light than the sun !
Ok , not that much but the panhandler that hangs out on an intersection median strip I go by keeps yelling at me to turn that fcking light out ! I also have a couple red taillights that rapid flash and one can stun small animals and possibly a panhandler. I have trouble seeing after looking at it just to choose it from other modes.arrrrr

[sternwake]

Glad you caught the Fedex truck.

Did you battery assembler advertise what cells they use by any chance? Could they be 21700's? They are so much more economical, but if the battery enclosure was designed around 18650's then they cant easily swap to the more economical cell with greater capacity.

I attached my old Nitecore HC50 to the chariot. it has some red leds, and a flashing mode. I forget to turn it on sometimes in the daytime, but at night there is a pretty healthy red glow behind the chariot. I did the ride until after dark tonight to Beeping ESC mode( low battery) with both Armytek and Sofirn right angle headlights. it would be great if they could maintain higher output, but they both thermally throttle. The sofirn will go back to turbo with a double click and the armytek will go back towards turbo2, with a single click, and when both are at or near turbo, light levels are impressive, but when they throttle, it is a bit disappointing. Certainly enough to see, the road surface, but more would be better.

I charged the new Samsung 6S1P 50E to 25.2 volts until amps tapered to less than 0.1, and put it on Big red booster, and Dialed up 9.8 amps input to booster.

The input amps keep climbing as it is a constant current output, and I kept dialing it down, ever minute or so.

The big red booster's fan came on for the first time after a while. it is pretty high rpm, I'd guess 2500. I will test this with optical tach at a later date.

basically I was starting out at about 215 watts charging my Esk8 battery and by the time the Samsung 6s1p had fallen to about 20.5 volts, My IR gun had found a 58.8C temperature on the end of one cell, and I quit the test, and foolishly did not record the Amp hours delivered.

The Continuous Discharge Rate of a cell, is determined using a single cell in free air about 25C ambient. The CDR so the maximum amperage a cell can be discharged at without overheating before it reaches it's 2.5 minimum voltage spec.

The Samsung 50E, and most energy cells are rated to only 60C. Most power cells are 75 to 80C.

My 58.8C temperature reading on the end of a cell was taken through one layer of Tesa tape, and one layer of Kapton tape, and one layer of clear PVC heatshrink, So the cell could have exceeded 60C.

My battery pack started around 25C from being inside the house, but the garage is 32C.

So I basically pushed the battery a bit too hard, and if I were to simply plug it in, dial up 10 amps on the input, it likely would have greatly exceeded 9.8 amps max, and 60C before the BMS cut power. The BMS has a little spot on PCB for an NTC temp sensor, which would be good to have if intending to push this pack this hard on the regular,

Just before removing it from booster I saw about 175 watts, which is still a very respectable charge rate but I started about 215.

I think this 6S1P battery, and the white booster, could be set to 160 watts or so and not overheat either the battery or the Booster, and drain from 4.2 to 2.8 volts per cell without overheating. This is probably the most effective compact portable charger method I have. I could fit the battery in one cargo short pocket and the booster in the other thigh pocket, and charge at upto 160 watts, and likely return somewhere close to 95 watt hours into my 324Wh BAK45D main battery.

Not too shabby. That should be good for at least 3 additional miles towing Fiona at near 20MPH.

But this 6s1P was made for the soldering iron which can only draw 82 watts, and only briefly. This was just a test. If I were making a battery for portable charging I would probably make a 9s1P of a higher CDR cell, but if going there just make another 10S1p battery and plug it into the charge port as we roll..

of course it would be better to not have to stop just to charge at all, but We do stop at parks and lookouts anyway.

Now my 3s4P 50E with 12 cells, has double the watt hours, and the lower input voltage makes the booster work harder, but the battery should be able to handle 35 amps continuous output without overheating. The whitebooster is then the limiting factor with its 15 amp fuse on input and 10 amp input rating.

The Big red booster is just too big for being a good portable charger, even though is seems to be rated for 40 amps input.

One interesting with Big Red, is it has a temperature sensor in contact with the heatsink, and when the fan first fires up, it only runs for a second or two, then shuts off, then comes back on, and basically cycles more off than on, but then becomes similar in both on and off times.

I put a blob of thermal grease on the sensor so it could better sense the heatsink, but it still cycled on and off, and the heatsink did not seem all that warm to the touch. Bare aluminum so hard to get a good reading with IR temp gun.

I am charging my 3s4p 50E back to full from a 5 amp bucker, and will go charge the esk8 battery from Big red booster, see how fast I can charge esk8 battery from it, upto 10 amps output anyway.

[sternwake]

I was able to push big red to 36 amps input and about 9 amps output, but it plateaued there with about 12.2v reaching it.
Was briefly touching 400 watts charging but this tapered pretty quickly and it went from trning 30 watts of power into heat, to nearly 65 watts as it got hotter and hotter

it is rated for 40 amps max.

There is a 3rd potentiometer for ;low voltage protection; on the input, and I need to play with this more, as it was limiting output until I twiddled it, but I kept spinning it hoping to get more than 36 amps input and it said Nope.

Charging at 360 to 400 watts, around 9 amps (1C for 10s2p of BAK45D) ) depending on Esk8 battery voltage, is acceptable. I'd like to have big red in a casing with a bult in meter and finger twist potentiometers and better ventilation, but that's another project that sounds great but will likely never happen.

CC/CV Booster charging from 12v nominal is the limiting factor, but 150 to 250 watts is hardly trickle charging.

Being so 12v nominal centric is a hard habit to break.

[sternwake]

   


Voltage booster mania.

[sternwake]

I strapped the enclosure housing my DMEGC 10s2p to my  board to my deck between my feet, both at 42v, parallel them through my new 14 awg XT90 to 5.5x2.5mm adapter, and went for a few mile test run.

All went well.

Decided to top up both batteries and lqter go for the longest post dinner cruise yet.

Found the dmegc was not charging and had to remove enclosure and reseat the fuse.

When i was returning  the encloaure gasket, there was a giant spark, a pop and a flash

.    

The 5.5 x 2.5 mm barrel plug found a conductive inside corner to complete the circuit.

So we went for a short evening cruise instead

[sternwake]

I Soldered a new 5.5x2.5 barrel lug connector to 14AWG and all is well.  I realized when doing it, that I likely never even tried to solder the tinned negative 14AWG wire to the contact, when I had the intermittent issue.  The positive wire was soldered first then the negative was held in place by it. So I basically forgot, and seemingly  never even soldered the negative wire in in the first place.

Wonder if I had been drinking.
Blame the beer.

I have ridden the Skate with range extender battery strapped to the deck, but didn't actually go far enough to where I needed the additional range  I went about 7 miles and returned to 40.04 volts on both batteries.  

The next day I knew I was not going to go far enough to require more capacity, and just removed the turtletop range extender, and it remains off.

My electronics Guru friend has a good sized Bluetooth speaker, that he finds incredibly convenient and says it is loud enough and sounds good enough that it gets a lot of use by himself and his wife.  Battery life was about 6 hours when new and had fallen to 3 recently.  I asked him what battery it had inside.

Eventually he opened it up and found a single 18650, rated at 2200mah.

He said there was room for 4 18650s in the battery tray, and sent me a photo,  
I Said if he  cut out the plastic corners and it looks like 4 21700's will fit side by side.

He agreed and I had him order 4 EVE 58E to send to me to spot weld together into a 1S4p. EVE 58E is basically the current  top performing 21700 Energy cell at 5700mah capacity and a 16.8 amp CDR.  Some Vapcell 21700's might have slightly more capacity at super low discharge rates, but their cycle life is questionable, and the base cell they rewrap can change at any time. 

I just finished building a 1S4P of EVE 58E.

22.8 amp hours
82.08 Watt hours
Max discharge rate 67.2 amps

Well, I only ran 18 awg wire so that rating of 4 58E cells in parallel is a bit tongue in cheek.

I did use 0.2mm THICK 10MM wide copper under 0.1mm stainless steel sandwich.
   
   
   
   


The small green PCB is a BMS/ protection board, to prevent over charge or overdischarge and overcurrent( 14 amps)

I am leaving this for him to solder to the 18 awg wires  from battery in an orientation which makes the most sense, and solder the wires to power the load and perhaps to ad additional separate charge circuit, to bypass USB micro charging. 

 These cells are rated for a standard charge rate of 1.12 amps each so 4 in parallel is 4.48 amps.  max charge rate is 5.6 amps per cell, but max charge rates are a bit of a never go here unless it is an absolute emergency and you do not care about battery longevity thing.

He sent me 4 Additional Eve 58E as a gift, so I am likely to build a 3S1P 11.1v nominal battery from them.  I have 2 other 3s1P batteies, made from 2000 mah  10 amp CDR 18650's, that still work surprisingly well and get a LOT of use.  but a 3S1P of Eve 58E will have almost 200% more capacity, and is only a little bit bigger.

I was gonna make a 3s1P from EVE 40PL,  4000mah 70 amp CDR( to 80c temp cut), using the  same 40 amp 3S BMS I used on my Samsung 50E 3S4P. 
 I honestly do not need a tiny 12v battery with the capability to pulse 70 amps. 

So I will need to find a task for those 3 extra Eve 40PL's.
I also have 10 more BAK45D I can make into a 10S1P.
And I have an Eve 40PL 10S1P at the half built stage already.

I have a Fiberglass  enclosure built for my lightweight mini esk8.  Pretty close to being done. 
 it is housing my old 10s2P right now for my turtle top range extender.

That enclosure has a huge heatsink, built for two older V ESC's, 
I still have a bad taste in my mouth from trying to get VESCtool to work properly and am reluctant to commit the frustration of likely failure.  These old vescs require a much older version of vesctool to work and I am not confient in my ability to down load the right version and the firmware and then getting the motors to detect properly and all the other stuff I failed at previously..

I have ordered a newer version of the ESC I now have ~2500 miles on, which is said to have even stronger brakes.

I plan to put this new ESC with Fancier remote into the rolling gupp, y and the older ESC into the Mini enclosure.  I have two different sets of hub motors I can use to power the lightweight Mini worn 83mm( now about 76mm) and the Puaida motors with 90mm sleeves.

 but I need to finish the 10S1P Eve 40PL, and then get all the wiring sorted out.

The lightweight mini has such a short wheelbase that it will have more torque and top speed than I want it to have with either set of my hub motors, but it should fit nicely into the kayak hatch,and it should  have at least 6 miles of range, towing Fiona. 

The weather is getting cooler and the water does not look as nasty now that the rainy season appears to be over, and I need to rekindle Fiona's interest in Cormorants and make every day with her as good as I can make it for her.