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

[sternwake]

Does your charge port read voltage?

My 7s2p bms does not, but my 7s1p does.

The bars remaining is as you know misleading.
I am at a park now 4.5 miles intoo a cruise, and still have 4 bars of 4, despite 10 miles of range. It will fall to 3 bars accelerating and pop back upto 4 coasting.

I don't know why i have range brain as rarely drain the battery to the level the esc atarts beeping.
I think we are just getting bored with our regular routes.
There are just some areas where traffic, narrow bumoy sidewalks with wide cracks just make it a bit stressful. I do not trust drivers herd, and many elderly simply should not be drving, and seeing Fiona in her chRiot has hem brake to a halt and gawk, with driverz behind them ragingbat their phones and everything.

Really with all my power tool batteries, boosters, and my old 10s battery, I can roll farther than my legs can handle. Than kfully my motors seems to stay under 161f, but florida is flat. the llongest stespest hill is a bridge.
i
Fiona also is wanting to get out and stop and sniff and just sentry the zone .ore often lately

I fear her age. and all her lumps and bumps, so if she doesn't want to roll, we stop.
Rarely, she refuses the offered chariot. So i go for a short ride alone and when i come back she wants to jump in and go.

[rvpopeye]

Don't know , haven't checked the charge port for voltage yet . Will do.
Tool batts are in the "long range" plan for sure.
I'm getting a little bored with my safe travel options here too but that won't be an issue when the rig is moving again....
I am liking the relaxed cruising at 10mph though. I can pay more attention to the sights instead of the bumps and pavement cracks coming at me at 20mph. I have turned around for iffy trails. I'm not going to risk ruining the day , bike or me ! Riding in traffic is generally crazy even uptah camp. Passing on a hill and /or on a curve or 6" from my elbow etc. ! And I really do enjoy the exhaust of a too big pickup flooring their manhood lol
Too funny about the old people, wait uhhhhhh I'm an old people.

Have a good ride today Bud !
I'm picturing you helping with the barking at the cormorants..

[sternwake]

Unfortunately, Fiona seems far less interested in barking at birds these days. She also does not seem to enjoy staying at at our watering hole for very long anymore. If I stand up to stretch she is like 'OK lets go!" jumps off the bench and just starts trotting the trail out of there.
I have to quickly gather her water bowl and my bottle and load it and catch up to her. It used to be like pulling teeth to get her to leave there.

I did have some words with one of the self important HOA members about rolling the crushed shell trail a few weeks ago, which really fired up my misanthropy. If she confronts me again I am afraid of what I will say, as there is nothing I hate more than a self important halfwit drunk on their sense of authority and constantly needing to be a victim, constantly seeking their villain.

Technically riding this Esk8 is illegal in Florida, although I've rolled by many LEO's without issue, but all it takes is one to ruin my day.

There are kids on the powerful Ebikes like Surrons tearing up public areas and sidewalks who are going to ruin Ebiking for all, and any PEV in public for everyone, even Us grey hairs who just want to cruise relatively slowly and alone away from all the hustle and bustle.

A lot of my speed is determined by how much breeze I desire in order to not sweat my balls off, but road surface quality plays a big part too, as does traffic avoidance. if I can go 25 in a 25mph zone then my chance of a driver tailgating me goes way down. They feel safe in their glass and steel cages tailgating me with their phones ot, but it is nerve racking knowing they are back there. Some of them get super close just to Video Fiona and have no idea how dangerous it is, and some even if they possessed an inkling of consideration for others, wouldnt care, and some would do it just to be the douchebags they feel the need to be on a regular basis.


Sometimes when the surface Smooth it is just fun to go fast, and I swear Fiona often loves the speed too. She will look bored when we go slow , but at 20mph or faster she is grinning with her ears pinned back and her bark changes from the bored bark just to bark, to the bark to be heard and seen bark, like

"you fools have to walk, haw haw!"

This is the slowest time of the year, tourist wise, in Florida, and it is still pretty busy.

Crossing the north draw bridge to the key was not as bad as expected as there were no pedestrians on the narrow sidewalk, and little traffic whizzing by at 45mph, but I still have to be vigilant. I want to cross the South Bridge, but the draw bridge portion is really rough and very loud under my rear urethane wheels. Supposed to walk bikes across it, and there is enough of a gap that my skate could potentially roll over the side. It is so busy with pedestrians and such that it just has not happened, and the sidewalks on the other side are all pretty narrow and rough, and I hate the sidewalk cracks. So we have not yet gone.

So basically we are bored with the regular rolling zones where we feel relatively safe from the stupidity and narcissism of humanity.

If I had rear wheels with pneumatic tires I would not worry about road surface quality, but Pneumatics means loud gear drives or belts, and I really like the Silence of the Hub motors. There are some hub motors with solid rubber 8 and 9 inch tires, but I would need to get a Different ESC and maybe step upto 12 or 14S just to be able to go 25mph, and those modifications would cost nearly as much as buying a whole new prebuilt ESK8, and I take pride in DIY.

Built, not Bought.

But the Built is way more economical, and building is so time intensive.

And when Fiona is no longer with me, I might lose interest in rolling at all.

I occasionally roll without her now, and it feels like I am cheating, and just want to get back to her and experience her joy at my return.

[sternwake]

I finished up my 3s4p Samsung 50E tonight.

It is 11.1v nominal, and 20 amp hours., so 222 watt hours.

My 12v nominal 22AH AGM is 264 watt hours when it was new.  I think I got it in 2019.

Here they are side by side.
   

That AGM was just barely able to start my engine by itself, when it was new.

My Samsung 50E 3s4p is limited by the 6$ 40 amp bms.  It can probably handle a 60amp surge for a second or 2. I only used 14awg , unlike the dual 8 awg on the AGM.
I wired a 4 pin JST connector to it, so I can see individual  parallel group voltages, and 'hobby chargers are designex to balance lipo batteries using this connector.

This BMS is supposed to passively top balance. In addition to the over  current, short circuit overvoltage/undervoltage protections.

Quality cells with good connections should stay in balance on their own until they start aging and differing in resistance and capacity.

BMS use little resistors to bleed very small currents off the cells which reach 4.18v first when charging,  but this is not foolproof.  If a p grojo exceeds 4.25v the bms disconnects the charging source.  the charger light might go green, and the human thinjs all is well, but one P group or several could have been well below their full charge voltage when  the bms cut power

So when a 10s battery which shoukd come off the charger at very close to 42v, but is well below that, it can be a sign the balance is poor, and the balancing resistor is not abke to bleex off enough voltage from the higher  voltage  cells fast enough.

My 10s BMS' are supposed to start balancing at 4.18v, so when I want to balance, I set my charger to 41.8v, and I limit amps to very low levels, and  let it go for many hours.
.

I've not tested this BMS.  
Kind of like with lead acid batteriez, one needs to be smarter than their' smart ' charger, with lithium one should at least be aware of what their BMS is capable of and how it works., or is supposed to work.

   

[sternwake]

I need to drill and tap my heatsink for the white Voltage  booster but I wired it up.
   

I removed the 18 awg leads and replaced with 10awg on the input, 12 awg on the output.

I used an XT90 connector on the input, so that I can use a  XT90s antispark from the donor battery.

This booster will cause a big spark when hooked up to power, which can destroy the connector with repeated sparks, like when hooking up an inverter, as the capacitors charge up.

The xt90s with the green bits has a capacitor between the  bullet receptcle contact on the positive pole that allows one to slowly charge the capacitors and thus prevent the spark.

There have bee  a few times where I forgot to charge my Esk8 and 150 watts was too slow, so I thought it was about time to get the 420 watt booster available for duty.

This white booster says  10v is minimum input voltage.  thats 3.33v per cell on using my 3s4p 222 wh battery.  Leaves a fair amount of watt hours on the table.

Hoping less than 10v inout  does not destroy booster.

My other boosters spark, but not too badly and I just use APP connectors on them.

These white ones are set at 18v output from factory. but the current limit potentiometer was well over 6 amps.  Remember the potentiometers are ccw to increase and CW to decrease both voltage and amperage.

Set output voltage to just above the battery voltage, not the full charge voltage on iinitial run. Then dial down amperage, then disconnect battery and dial voltage to desired level at or near full charge voltage with no load on it.

Then plug it back into battery and dial up desired amperage.

Failure to be cautious can smoke the booster, or something more expensive and hard to replace.  
The voltage pot above 36v is super touchy. 
Dialing in 42v exactly unloaded is kind of hard, and it gets more difficult as one approaches 60v.

[rvpopeye]

It will be a while before I get all the parts and pieces but will double check everything .
I already have (new to me) sparkless xt90s on my parts list to have onboard .
Plus xt60s , APP45s , 6ga SB50s I'm running low since the solar rewire last year..ya know just in case lol.

Scratches for the rider of the chariot and thx for blazing your trail for me arrrrrrrrr arrrrrrrrr.

[sternwake]

When Soldering the Amass XT series connectors( and there are a lot of xt60 fakes) and they are often already on the Chinese  assembled batteries, Don't forget to put the tailcap over the  wires first, although some prefer heatshrink. 

Mate the male and female connectors to Keep the pins aligned through the heating and cooling process.  The Nylon is pretty resistant to melting but.... it is good preventative medecine.

There are little XT30's too but getting 14awg wire onto these is a bit of a challenge to do cleanly.   They are a nice small connector though.


My 7s2p 18650  enclosure with the White booster has a Mosfet based Antispark switch like this.  It's  actual pushbutton is a latching switch.

I think these have a very small parasitic draw, well below my ability to measure.

https://www.mboards.co/products/power-sw...off-button

My 7s2p is only 103.7 watt hours.  I keep thinking about ways to fit more capacity inside this portable battery to battery charger, but then remember I have not even bothered using it, except to test it.

My 3S4P has 222 watt hours and the white booster attached to heatsink takes up the same amount of space, but there is some fragility involved.

[sternwake]

I drilled and tapped my heatsink for long m3 screws which would then elevate  the finned heatsink about 5mm over  over a table surface onto which it is placed.

I spread thermal grease on the mating surfaces and tightened the booster to the heatsink, then started testing it, with my newly constructed , fully charged 3S4P 11.1v nominal Samsung 50E  battery pack as the source.  It was set to 41.8v output, and feeding my 42v max ~55% depleted ESK8 battery.

I started slowly cranking up the Amps, with wattmeters on input and output sides, and the heatsink started getting pretty hot despite good fan flow blowing over it..

At ~26 amps input it shut down and I looked closely, and there is a 15 amp fuse on the input which blew.

   

I then searched Ebay for the product description and then all the other listings of the same product, and one of those listed more detailed specs, and said 10A input max, not just 10 amps output max.  So apparently if one  feeds  this 58 volts, and output 60 volts, then it can be considered a 580 watt booster.

Feeding it 12.6v, then apparently it is a 126 watt booster.

so I was up at 26 amps input when its 15 amp fuse failed with my 3s4P as the source.
 
 if 10 volts is its minimum input voltage and 15 amps max input fuse is the( eventual) limiting factor, then this booster is reliable only for 150 watts, like my favorite blue booster  with its 24v 50mm fan bridging its heatsinks.

So basically feeding it 3S voltages  from a battery capable of 40 amps continuous output, even with a big old heatsink, I am limited in available output current to basically little to no Better than my other boosters, which is disappointing.

The 7S2p battery with its 29.4 to ~21v range should have it be good for  294 to 210 watts.  I have my &s2p enclosure portable charger,  set for 250 watts output and likely need to open it up and dial it down some.  I have that one attached to a thick piece of aluminum and then a smaller finned heatsink.

i guess I am going to remove that little fuse, replace with some wire, and add an inline fuse on the Input 10AWG.

There are  voltage boosters rated for higher input amperage, but I don't know If I am going to pursue  high amperage portable charging devices any more than this, considering I have not needed more range than my ESK8 delivers in quite a while.

I was hoping the 222 watt hour 3s4P was going to be able to  charge my 324 watt hour 10S2P esk8 battery at 250  to 420 watts, and that is not gonna happen for more than about 2 minutes with this booster.

But a 150 watts charge rate is not the end of the world either, it just takes a bit longer and often, there is no rush anyway.

[sternwake]

I decided, without  expectations, to see if it was possible to desolder that rectangular fuse while the PCB was still attached to the large finned heatsink.

My Miniware TS101 'smart' soldering iron is capable of 82 watts when fed 25 volts, and my 7S1p battery was discharged to 25 volts, and the chances that 82 watts seeking 400 degrees C  could liquify the solder holding this fuse on, were exactly zero.

I was holding it on for 40+ seconds watching battery voltage and the wattage drop, and zero chance. 

The heatsink was just starting to warm up when i gave up..

I was only trying to avoid removing the PCB from the heatsink, as the thermal grease is as annoyingly messy as Antiseize grease is, and it is not really cheap either.

When drilling and taping the heatsink for m3 screws, there is danger of breaking the drill bit, when it reaches the fins.

Driving the m3 tap all the way through makes for some pretty weak threads as well, So I like to drive the tap maybe 2/3=3/4 the way through, and let the screw finish deforming the aluminum / cutting the final thread or 2,  and allow for some more thread strength.

   

Even when trying to aim for the gap between two fins,  there can be unpleasant results, but this m3 screw has some good grip.


Much like 'range brain' I cannot seem to stop thinking about charging speed.  I rarely need to be able to charge faster than I can achieve now, but what happens when I do?

My 5.5 x 2.5 barrel plug charge port is rated to 10 amps continuous, though many are just 5.

I actually have 2 of these charge ports on my esk8 enclosure.
 One, for now, is unwired, and is just an enclosure hole filler.
There used to be the power button for the ESC in this hole. but this ESC with a power button would decide to randomly lose connection with the remote, and with no power button it never has. 

I can spin one of the hub motors to turn the ESC on, and it has an Auto off feature when there has not been any throttle or brake input for a period of time, about 2 or 3 minutes I guess.

I also employ a 'loop key', which is an XT90s  on the positive cable from battery to ESC.  both + and - contacts are bridged with 8AWG  Pull the loopkey and the ESC is mechanically disconnected from battery.

Sometimes roll to start does not work properly and I need to pull and reinsert the loopkey.  No big deal.

The power button is needed to initially pair the remote with the receiver, but I have never had to do this.

So 12v DC and 11.1vDC nominal input voltage to my booster chargers is the main limiting factor to charging at 150+ watts.

The Blue booster just says 150 watt max, and just works fine at that output, whether fed 12v, 18v nominal, or 25.2v nominal.  I do have the 50mm x 10mm 24vdc fan hooked to the input, and I  can dial it upto 160 watts output, which is respectable.

The red booster, I cannot fit a fan onto it AND adjust the voltage or amperage potentiometer while the fan is running.  I've been using these to charge the 7S batteries, even though they claim 400 watts.  In reality they say:
 
Max. Input Current: 15A (please enhance heat dissipation if more than 8A)
Max. Output Current: 12A (related to the input and output voltage difference, the greater voltage difference is, the smaller output current will be. please enhance heat dissipation when current is over 7A)

The White booster has the 15 amp fuse on the input, which I blew at around 26 amps input, and the heatsink was getting hot quickly when that happened.

95+ % of my Esk8 battery charging happens on the bench with my 100 amp adustable voltage powermax holding my Deka AGm's at 13.6v then the blue booster feeding upto 150 watts.  Basically I charge as slowly as posssible but as fast as neded before I expect to want to ride again, or goto bed and not leave it plugged in while I sleep.

I dont want to use two boosters in parallel through dual charge ports.  Bad things might happen, or they might not.

i would like to be able to charge at at least 1C, which for my BAK45D 10s2P is 9 amps at 42v, or 378 watts.  The BMS on this battery says 10 amp max charge rate.  I did add a heatsink to the BMS , but dont expect that to increase that maximum, just delay the max temperature it will  reach.

The BAK45D says the max charge rate is 13.2 amps, or 26.4 amps for 2 cells in parallel, but this will reduce battery longevity, and can likely only be safely applied for a short while, say between 15% and 60% state of charge, then throttled way back or the Lithium Ions will not have anywhere to go and start growing dendrites which can eventually pierce the separator and short circuit the cell.

I certainly dont need to approach 26.4 amps charge rate, and my BMS is only good for 10 anyway.

Enter the large '1800 watt booster'
https://www.ebay.com/itm/365864942627?var=635642574290

Says 40 amps max input, so at 10V, that should be 400 watts.

I had one of these boosters many years ago.  I though I could run 24v hedge clippers from a 12v battery, and this did work, until the hedge clippers hit a big branch.  Then it quit and my inline wattmeter went dark.  not designed for such a dynamic load it was late to compensate and then shot past 60V and blew the wattmeter.  That booster still seemed to work OK afterwards at low loads but i never trusted it, and I abandoned it in California and wish i at least removed the fan and the heatsink, but time was short and space limited.

Anyway, another one en route, and this will be the 7th voltage booster/ Esk8 battery charger that I will have.  It should allow for 400 watt charging from my 3s4P Samsung50E until it drops to 10v, 3.33 volts per 4P group.

I also bought two more of these 24v Delta fans.

These are what I have mounted to 150watt boosters and keeps them cool enough at 150 watts and 12v nominal input, and keeps them cool at 29.4v input.

Honestly, the Ideal portable battery to battery charger for me would be a 9s battery feeding a 10S battery, but a 9S battery is such a weird voltage it would basically be useless for anything else.

My 3s4P can at least power all my lights or fans or perhaps be able to assist in jumpstarting an engine.

[sternwake]

The Fuse resisted removal, even when not attached to the heatsink, so I just soldered solid 14awg across it and installed a Flag terminal ATC fuse on the 10AWG input and tested it again.

Fed from a 3s1P battery it held a 1 amp output as the input voltage fell to the low 9's then the BMS cut power, so it does not self destruct at below 10volts input, at least at 3.5 amps output anyway.

Been feeding my put to pasture DMEGC 26E esk8 10s2p with my 3s4P Samsung 50E at upto 170 watts and 15 amps input. The heatsink gets quite warm, and I got to keep lowering output current to keep input current below 15 as source battery voltage falls.

It seems the max 10 amp input rating is a good suggestion but not a hard limit if there is enough heatsink and airflow.

I am not sure of the minimum voltage I have fed the blue booster when asking it for its 150 watt rating, but I don't think this white booster is any significant improvement over the blue at 12v nominal input voltage.

The white booster being fed with the 7s2P is good for 250 watts output. The heatsink gets pretty hot, but the 7s2p only has 104 watt hours and cannot run all that long..

Now My Dmegc pack is nearly fully charged and I have no need for it to be.

I do have a pretty large Bucker I can use to charge the 7S or 3S packs

Still a potentiometer spinning nutjob.