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

[sternwake]

At one point, the BAK45D were available for $4.75,  but were tarriffed up to $6.85.

I got my 22 cells for 5.45$, iirc.

The EVE 40PL is another 21700 tabess cell, and stays a bit cooler than the BAK45D at 40 amps continuous and holds a higher  voltage for most of the discharge.

I noticed today that 18650batterystoredotcom, a reliable seller dropped their price on EVE40PL, from 7.25$, to 3.99$

That is the least expensive I have seen any tabless cell from a trusted seller, and I ordered 13.

The three extra will be for  testing welder settings, and if they survive, will be for a 3s1p 12.6v max, 11.1v nominal pack.  

I have made 2, 3s1p packs, from a  failed 7s1p 36$ esk8.  Supposedly 2200mah  18650 cells some little known brand. probably reclaimex cells when made into the 7s1p too.

 They actually work pretty well powering 12v fans and LEDs, but both have one cell which trips the bms low voltage.  I should have bought 23 BAK45d, not 22.

The Eve40pl is rated for 4000 mah, but at low discharge ratez(0.2C is standard)  exceeds 4100mah.

Vapcell is a pretty trusted cell rewrapper, and they rewrap the 40PL as their S41, and call it a 4100mah cell.  For a while Liion wholesale dotcom had the best deal, selling the S41 for 5.99$, so when I saw the 40PL for 3.99$, I basically ordered immediately as I figured they woukd sell out quick  at this price


I have a new fiberglass enclosure 98% finished, designed for a 10s1p flexible pack.

I had made the Molicel P42a 10s1p for this enclosure, but it got submerged and ruined when I dislocated my shoulder.  It was a performer though, way more torque than my dmegc-26r 10s2p.

So I ordered a new low profile mini fuse holder, a Dumb Daly BMS, and some more 70mm wide barley/fishpaper, and 0.1mm   copper sheet too.  

It will be nice to have a backup  and a small lightweight esk8.

I meant to make a fiberglass enclosure lid today, so I can seal it much much better.
I did cut the fiberglass, but the skate will not be ready to ride tomorrow either.

I did weigh up and mix and apply some JBWeld to my twitchy truck to better contain the bushing.  The urethane bushing does not compresss, it deflects.  My older truck had this built in , and felt far better, and this is the biggest difference, other than the size of the motors and wheels, that I can see, so perhaps the jbweld containment of  hanger's boardside bushing will return some stability, and perhaps prevent a streetfacing deathwobble roadrash injury.

[sternwake]

I put my battery and ESC, back in my enclosure, and temporatily sealed it better than before, but by no means as well as I'd like if caught in a rainstorm.

We rolled about 11.5 miles on a single charge after dinner. The BAK tabless battery continues to impress.

The JBweld bushing encapsulator modification worked wonders at reducing bump steer, but attenuated the twitchy factor only slightly

I got over excited when one of the best 21700 power cells dropped to 4$ each.

Today I noticed a very good performing 18650 power cell dropped to 2$ each.

But I managed to resist.
These perform as well or better than the cells which came in the base model power tool batteries from Makita and dewalt and milwaukee from the last several years.

https://www.18650batterystore.com/produc...0a-battery

I want to rebuild the cordless vaccuum's 7s1p battery with these,, as.I notice it already losing caoacity and grunt with whatever junk cells they used.

I notice my makita batteries losing some run time, but not a huge amount. My Ridgid batteries seem to be retaining their capacity well. The 4.0ah uses Lishen cells. The 2.0 ridgid Btteries, .im not really sure of any noticeable capacity loss, but they use EVE 20p.

Torquetest channel on youtube is modding some. batteries using new Tabless cells, and getting serious gains in tool.performance. The EVE40pl custom batteries are even outperforming The new milwaukee Forge packs, which come with the venerabe Ampace JP40.

BAK, Ampace, and EVE, and Sony/ Murata, Samsung, and LG will all have tabless 18650's out pretty soon, and the big power tool makers are designing tools that can take advantage of the extra power these cells can deliver.

I was kind.of marveling looking at my BAK45d battery today, and how much energy it can store.

[rvpopeye]

Prices dropping , power capacity going up , terrible situation !
On a different note. Heads up Renogy is releasing a solid state monster batt.....

[sternwake]

Very interesting. Solid state is a game changer, but is also a marketing buzzword.
There were a few other 'solid state' batteries on the market that proved to not be true solid state.

Not saying the Renogy are, or are not, just that I am suspicious.

My 13 EVE 40PL's arrived today, but it will be a while before i can begin to build a 10s1p with them.

My cheapo purple spot welder, suffered a burnt trace, on my last battery build. I was able to bridge it with some thick copper from a Van related project, and returned it to function.

The Zee Lipo weld battery was fading fast at the same time and I had to use higher pulse durations, and it was getting super hot, then started leaking electrolyte, and now.I have no weld battery.

I do have a backup purple spot welder, and I could try and beef it up, but I still need a welding battery.

When I used my AGMs as the weld battery, they proved too powerful for my red and black welders, even with low mS pulses.

I could try the Repaired Purple welder on my AGMs, but it too could blow up.

My Zee 3S 5.2AH lipo was the cheapest available. I'd like to have a higher end weld LIpo, and would love to use thicker copper than the 0.1mm I used on previous builds and which maxxed out my equipment.

A quality weld lipo is gonna be 50-70$, and i still have a junk welder.

I noticed The guy I bought my BAK45D's from, started carrying a different brand of spot welders.
AwithZ, and they have many different ones with different power outputs.

He just released a video, with the 159$ lowest power version, and was just able to weld 0.2mm copper with pure nickel sandwich, and nickel.plated steel instead of pure nickel, is easier to weld.

https://youtu.be/gMzCUJ00xzM?feature=shared


I only have plans to build this one last EVE 40PL 10s1p battery, but I want this welder.

Want vs need though.
Hard to justify when I am jobless, and a hospital claims I owe them a quarter mil for my stents.

The BAK45D battery continues to impress. I don't even bother to charge it upto 42v anymore.
I don't need the full range available, and have plenty of torque to bark up the hood with Fiona at less than full throttle.

[sternwake]

My purple spot welder is looking like it just retired.  Its lithium polymer weld battery started leaking electrolyte on my last few welds.on the 10s2p BAK45D  A04 pack I last made.

An AwithZ capacitor based spot welder is en route.

This outfit apparently has 32 patents with regards to spot welders, and has adjustable 'preheating' functionp, and upto to 3  welding pulses with adjustable interval, to really dial it in.

The model I am getting is their second Least powerful, at 14.4kW, and it can weld 0.2mm copper, by itself, without copper welding flux.  The most powerful model is 69kW or something similarly crazy overkill  number, unless.one is welding super thick copper.

https://diy500amp.com/products/awithz-p2...er-14-6-kw

This guy ^ has better prices on these welders,  than aliexpress and amazon and ebay, and  ships them UPS out of Florida.

He is where I bought my BAK45D's from, that were shipped within the hour, and arrived 22 hours later.  He is also the guy who imported the Mac Daddy Dalai Lama of 21700 Power cells, The Eve 50PL. He also has the best power 18650 currently available, the Ampace JP30.

Eve 30pl and BAK 30D are not in production yet, but promise to compete with or perhaps even outperform  the JP30.  

I only had plans to build one more Esk8 battery, A 10s1p of EVE 40PL cells, but plans can change.


A while back, I placed an order for 105mm Meepo brand dual 540 watt Hub motors for $ 189. 
 But then the de minimus exemption expired and they were subject to 130% tarrifs, and they never shipped, and they let me cancel the order.  I found the New old stock Puaida motors on ebay for 130$ and all was well.

I noticed that Amazon started stocking the 105mm 540 watt Meepo motors for 159$, then they started offering a 15% off  coupon, and for a day or 2 a 20% off coupon, and I could not resist.

When they arrived I put their 105mm sleeves on my Puaida motors and waited on new MR60 phase wire connectors to arrive.  The added diameter reduced torque and the brakes too, but they were significantly smoother over the rough stuff, and top speed increased a little.  Motors were getting hotter, as was ESC heatsink, and range suffered too, but was still adequate.

After I cut off the mr30 and installed the MR60 phase wire connectors, I found the hanger which holds the motors  woukd not.fit my existing trucks baseplates, so I transferred the Meepo motors to the Puaida hanger, and buttoned everything up.  I was surprised to find the Meepo motors weighed 30 grams less, each.  I returned 105mm sleeves to the new motors

A solo roll revealed slightly more torque, but the brakes were much stronger.  I sought out a radar speed sign and  calibrated the  remotes speedometer.

I expected the new motkrs to perhaps better be able.to shex heat, but not realky perform amy differently, but I was wrong.  They likely have a different number of.pole.pairs and are wound differently.

My biggest complaints have always been weak brakes, especially when towing Fiona, but now I can almost lock them.up.

There is more torque too, from 5  to 20 mph, but less top speed,  than the Puaida motors.

The BAK45D battery gives me close to 10miles.of range, towing Fiona, cruising 20-22 mph on the straights, and does not  come.close to overheating, like my old.pack would.

My calvez are onnFire after 10mikes, so More range  is not required, but I would like to visit an area 7 miles away, one way.  I have ideS for paralleling old battery with new, and carrying a 7s2p powered 100wh 10s charger, and these in combo should  allow no less than 20miles of range, towing Fiona.

[rvpopeye]

I always look forward to your next report post ! No disappointment with this one
Meepo ? (Sounds like a breakfast treat LOL ) Hope little Miss Fiona approves ! No doubt in my mind she will yup yup.
The DIY500 link looks good ! Hope the new welder is the last one you ever need. A quick reliable source for cells too !

Following along , thinking of a second pack for the ebike. (mfg offers a drop in 48v12Ah for $330 .) I'm being careful to not over estimate the turn around point. I'm getting ~ 20 mi on a charge now , possibly more but hard to know for sure without running it completely down . I'm thinking a little bigger capacity for my backup to make my depleted 1st pack the turn around point to guarantee a relaxed return trip . It fits into my (aluminum) frame Thinking that 330 would buy a lot of cells for a diy ! Using 21700s is looking like the future (for now , seeing hints of an interesting aluminum based cell from tesla soon...) It's probably not gonna fit in the frame and require some rewiring an extra possibly different battery plug in connector .
Top speed is restricted to 20 mph , there is a controller hack but I feel 20 is plenty fast anyway !!

Is a BMS review coming up or do you think they're not really needed ?

Ya know,,,,I get a feeling the sea rig is in for some kind of a speed upgrade too ???

Carry on my wayward son. There'll be fun when you are done ! Don't let Fiona cry no more......alright , getting carried away here.
Latah Gatah ! Scratches for her majesty !

[sternwake]

21700's right now are cheaper, with a higher CDR and higher capacity..

I am not sure how Ebikes work with regards to battery swapping, or range extender packs.

Honestly, the prebuilt packs are hard to beat, price wise. The main reason to build your own is when you want to use known high quality cells and built them to a higher standards.

With DIY esk8, the The BMS is only wired up for charging. The esc itself handles the low voltage cutoff. This is done as the BMS cutting power, can be bugely dangerous, not only with the loss of brakes, but when one is braced for accelleration, and the voltage hits the threshold, and the BMS cuts power, then it is difficult to not streetface. It will almost always cut power when one is leaning on their front foot accellerating, and aoss of power causes one to fall. The more powerful belt and gear driven boards do not have great free roll, let off the throttle and it is almost like bitting the brakes.

On a bike, one is not.going to go flying over the handlebars if the BMS cuts power, and there are atill friction brakes to stop safely.

My weak hub motors have great freeroll, nearly as good as an analog push skateboard with good wheels and bearings.

With DIY esk8, one only needs a BMS to handle charging current, they can be a lot physically smaller, and fit into an already tight enclosure easier.

I am using Daly BMS's, dumb ones, as the smart BMS is always sending a bluetooth signal, and that paraSitic draw has killed many unattended packs. My BMS are rated at 10 amp charge, 20 amp discharge, but my latest model of same dimensions says 15 amps for both.

I have a smart JBD bms for 10-17s, and 15 amps charge, 30 amps discharge iirc but it is pretty big, and they have a smaller model i should have ordered instead.

Ebikes generally use energy cells, not power cells. The energy cells.in a 4p configuration can handle the draw without too much voltage sag.

I am using a 2p configuration in my esk8, so each cell needs to output more, so a power csll which will not.overheat, and not sag a lot.of.voltage is much more desirable.

Riding more sedately in cooler weather I'd get some morre range with some energy cells vs the power cells, but riding harder the power cells will actually provide more energy to the motors.

So cell choice should have a lot of factors considered. Price is a huge one of.course, but there are many asterix's involved in what is actually best for any given application.

Excellent data for informed cell choice would be max amp draw, average amp draw, and how the exiating battery performs with its cells. Often huge unknowns.


A lot.of.prebuilt battery packs won't say which cells they actually use, and.might not actually use the cells they claim that they do.

I am actually scared of my 2 7S prebuilt packs with their noname brand cells, and unknown build quality, hidden under the shrink wrap.

[sternwake]

Here are my ideas for range extension.

The easiest to me right now, is carrying a Ridgid 18v battery, an CCCV150 watt vBooster. Set it to 41.90v, and just below 150 watts, and can get 63ish of the 72 watt hours in the ridgid 4.0ah pack into my battery. Thats good for about 2.8 miles of range riding normally, but if i go 14mph and accellerate slow, upto 4 miles.

I keep a fannypack in the chariot, and can fit many power tool batteries in it.

I also have the 7s2p, and 7s1p battery packs. I used to plug the 1p, i to the 2p via charge port while riding. These can power the same CCCV V booster, more efficiently a they have higher input voltage.

I can eek out ~ 145 watt hours from these two.

My old plastic 7s2p enclosure, is one day gonna house the 7s2p, and a 420 waTt voltage booster.

It is a half finished project, .mosly as the old battery got too hot and charging while in the parks at high rates makes a lot.of heat, and with new BAK battery, I have not needed more range, yet.

I have Not used the CCCV booster while actually riding and rolling. There will be some degree of dynamic load on it while riding and I dont know to what degree, or how it would handle it. especiLly the regenerative braking. Others have done it with 1200 and 1500 watt units on higher power demand builds, with a big feeder battery, and say they get super hot.

For a range extension pack of equal voltage, one can basically plug it i to the charge port of the main battery. They need to be very lose in voltage when paralelled, or more.current can flow than the BMS, or charge port fuse can handle.

My external.pack has an XT90s connector to feed the ESC. 10awg, bypasses BMS. This cir uit +, runs through a 'loopkey' which is an antispark XT90s connector, with its contacts bridged. Pull the key, and break the circuit..

I could put a second loopkey port onto enclosure, wired directly to the ESC, but downstream of loopkey. So basically ride one battery to the end,.pull the loopkey, plug in second battery.

It has a fused 16awg+ feed from.charge port to Main battery +. the - runs through BMS. I have both an Anderson powerpole, and an xT30 connector coming off BMS..

If I plug in additional equal voltage battery to charge port , from pp45, or xt30 there are basically 2 fuses and two BMS's between the batteries., and asking more than 10 amps from.this circiut would be unwise, but briefly possible, depending onnthe actual resistance of the cir uit and how much draw is on the main battery.

I.see the least potenial issues parallelling two equal voltGe bTteriez at the start of a ride, through XT90s, and unparallelling them when stopping.

Since i have the chariot, and we roll to cbill at parks, there is time.to just use the CCCV booster while we bark at cormorants.

I would not want to have to stop on a sidewalk somewhere just to charge though but it woulld be better tha walking..

My old rigid 10s2p DMEGC, strapped to deck between feet plugged into charge port is likely the easiest charge and ride method. Fuses might be blown.

The best would be paralleling through 10awg and XT90s when batteries ars equal voltage, and charging them separately.

For ride to charge somewhere, then ride again home the lower voltage battery feeding the main battery through a CCCV booster is great option.

The lower voltage battery feeding the Vbooster does not need to be made of power cells, cheap energy cells are fine, an inexpensive .prebuilt battery is likely fine for this task.

I have one booster capable of 10 amps output, so at 42v, so 420 watts. Ive rarely exceeded 160watts.

The BAK45D max charge rate is 13.2amps, so at 2p, 26.4 amps
Safe to say I'll not be charging it at 1100 watts anytime soon.

[sternwake]

The AwithZ P20b spot welder arrived.

It laughed at 0.1mm copper, 0.1 nickel plated steel sandwich using 10% of its available power.  This is the maximum my 21$ purple spot welder could handle.

I had to crank the AwithZ upto ~70% power t before I could properly weld 0.15mm  copper with 0.15mm nickel plated steel sandwich.

I tried next to weld 0.15mm copper with 0.15mm pure nickel, and 95% power was not enough.
One of the two welds would be good to great, but the other would not stick, or just barely stick.

I tried many things, but the positive welding probe refused my desires.  50ms preheating, triple pulse with different intervals, no dice. not happening.

I next tried 0.1mm  copper, doubled, with 0.1mm nickel.plated steel at 99% power,.and got 2  solid welds.

Copper has 4 times less resistance as pure nickel.
In general most Esk8 battery packs.use 0.2mm pure nickel, even the high power builds with 18s6p batteries.

Ill be running only 10s1p so each cell.has to work hard, and will get hot doing so, so I.dont want the series  connections adding to the heat generated within a tight enclosure.

The Eve 40pl is a beast of a 21700 cell with a 70 amp temperature limited continuous rating.
My  current  ESC can only pull 24 amps, 12 per motor, and is powerful enough.
The Eve 40pl is gonna feed two programmable  Vescs capable.of upto 50 amps each

[rvpopeye]

My 1st thought was using tool batteries ! My 18v 4Ah ryobi's in 3s config using ports from extra chargers for plug-n-play.

The new welder sounds like a good improvement over the cheapo. Hope it lasts forever !