SJEAA Meetings


Working hard on Analog Lithium BMS board.
– Using Toner Transfer process.
– Print reverse image on a LASER writer only.
– Iron or laminate to copper.
– Etch in Ferric Chloride.
– Drill holes
– Test
– Next version could have an Atmel processor.
– Pulsarprofx.com for Toner Transfer details.
– Trying out GBC H310 Laminator

Bought 30 more A123 Lithium cells
– Hand tested each one.
– They are used cells.
– Most tested at 95% capacity with a 35 amp load.
– Will retest at 5 amps to see what cut Peukert takes.
– Rotordesign.com/blog

HexaYurt Building
– Goal to have it half done by Monday or I quit building it and get a tent!
– Canvas K-Hinge makes for attaching all roof and wall panels together so tape is not needed.
– All panels are hinged to each other with canvas K-Hinge.
– Unit folds out in one continuous piece.
– between some panels a #10 zipper is sewn in so the joint won’t fold.
– Need some form of cooling.
– Spray bottle has been claimed to work inside Yurt for cooling.
– Rotordesign.com/bm

Purchased 8 Dolphin boards.
– Two needed repair.

Saturday Aug 29th, 2009 EAA Rally.

Move the SJEAA website!!!!

Was at Robogames during the last meeting.
– Took my self balancing scooter.
– Converted from 4 NIMH packs to 3 Lithium A123 packs.
– Charging it with my rack mounted 60v 10a CC-CV power supply.
– Just received a small 36v 10a switching PS for mounting inside the scooter for on board charging.
– Added a reclining camping chair and a joystick for steering in place of barstool.
– Used both barstool and recliner at Maker Faire due to poor solder inside the, brand new in the box, Joystick.
– Took the scooter to the Maker Faire as well.
– Will be taking it to Burning Man.
– Finally got a new wheel from the guys at the Tech Shop.
– Drunk employee crashed the scooter, cracked an aluminum hub and a wheel.
– I was never told of the crash.
– He rode it without consent.

Mapped all of the hundreds of components on the Dolphin board to a spreadsheet.
– This makes possible the ability to compare parts from one generation of board to another.
– Should help find the differences in parts between relaible boards and non-reliable boards.
– The goal is to find the source of the dropout issues.

Purchased a 60v 30a constant current constant voltage power suppply from Ebay.
– It was supposedly fully tested.
– The fan, one filter cap and a third part were shorted.
– Repaired it.
– Works great for recharging batteries during load testing.

Bill and I are building a Yurt for Burning Man.
– See Photo.
– Most are assembled with nylon strapping tape.
– We are testing Liquid Nails and canvas.

Scored a dozen important circuit boards for USE vehicles.
– Was suppose to be split up.
– Suddenly found boards on Ebay.
– Emailed owner and asked if I could buy them. He agreed.
– Pissed off a few people.

Got moderated on my own forum.
– 4 deals went bad. Me mad. So sad.

GV wants me to make them Lithium boards.
– Never seem to have any money.
– They want to own the schematic.

We need a place to meet on August 8th. Ana’s ??

Added note to SJEAA website that we won’t be meeting here Aug 8th.

www.frompatenttoprofit.com

Saturday Aug 29th, 2009 EAA Rally.

Truck has reduced range due to cell to cell variation in capacity.
-Deep cycling the pack only lasts for a couple of weeks.
-Tried to deeply overcharge the cells.
-Mostly worked.
-Killed two cells in the process, but ruined 3.
-Cannot really afford new pack in this economy.
-No cell auctions this year.
-Gels for Solectria’s might be a good alternative for either truck.

Developed a high powered Lithium bms board.
-Bypasses 3 amps easily.
-At 3 amps the special transistor stays cool!
-Tons of work to figure out how to keep the transistor from getting hot.
-Most amps bypassed on lithium cells that I’m aware of!
-With more work, could be made to bypass 5 amps.
-Limiting factor is how hot the load resistors get.

Purchased a 1991 Honda Accord with 200k miles.
-Should have had a blown head gasket, but did not.
-Instead it had many other smaller issues.
-Currently replacing a steel coolant tube that had rusted through.
-Cooling system has had only water in it.
-The car already has many new parts.
-Found a rats nest under the air filter.
-Engine had a sizable hesitation to it.
-Gas mileage was only 20mpg.
-Failing smog test at home with Bar84 analyzer.
-Analyzer turned 30 years old this year.
-Had to replace all of the hardened tubing!!
-Tubing shattered like pasta noodles.
-Removed ‘obstruction’.
-Now it passed smog with great ease!!
-“I’m free from the plug!!”
-Took Friday and Monday off to work on it.
-Should be finished with cooling system this weekend.
-Vehicle has flat spot and needs some emissions equipment work.
-Good online Honda groups.
– 5 vehicles is too many!!
-Thinking of selling the wagon and the motorcycle.
-Funds would pay off the Accord rebuild expenses.
-Would like to work up to an Insight or early Prius.

Finally signed up with AAA.

We’ve lost 2 local EV dealers.

Ruf Porche Electric using Thundersky cells.

– Looked at Coulomb chargers in downtown SJ.
One 208vac SPI and one 208vac Avcon charger were replaced with 120vac Coulomb units.
-Arguing about loss of 208v chargers in the 4th st garage with Tom Dowling.

Tom Dowling claims they will put in 208v Coulomb chargers when the connector standard is turned into a real product.

Coulomb rates:
$10 setup fee.
$15/mon for 10 night time charging sessions.
$30/mon for unlimited night time charging sessions.
$20/mon for ‘grid-friendly’ charging sessions.
$40/mon for unlimited ‘grid-friendly’ charging sessions.
$50/mon for unlimited chariging anytime.

– Titled, registered #2 truck.
Also ordered HOV lane sticker and San Jose parking sticker.
Ordered orbital buffer and supplies for polishing the paint.
Looking at Gel Cell batteries as they last a long time in the Solectria’s.

– Range on #1 truck was 12 miles.
Nicad pack needed to be shorted to zero volts.
Range and voltage is greatly improved.
May need to deep cycle a couple more times.
New 240v variac helped make recharging very fast.
This can only be done with flooded Nicads.

-The heater on the #1 truck works great!!

– SJEAA website updates
Added 3 links to DMV for the various EV stickers required for parking, charging and commute lane riding.
Will add more manufacturer and other links via the SFEAA website.

– Got rid of both S10 bumpers and the bed toolbox via Craigslist.

-My official weight loss for 2008 was 44 lbs.
Celebrated by having my first ice cream in many months.

– Made a schematic for the heating and air conditioning systems.
– Scanned and imported 3 different drawings to make the schematic.
– Used it to repair the AC and heater systems.
– The AC and heater never worked per the original owner.
– Air conditioning now working!!
– Heater has upgraded element and gets hot very fast.
– #1 truck will be getting an upgraded heater asap.
– AC had corrosion on the black box control connectors.
– Bad crimp too.
– AC works but connector is still intermittent.
– May have to solder crimped wires.
– AC increases output by the compressor running faster based on positon of temperature knob.
– The blower was on all of the time.
– Found wiring issue and rewired to correct blower issue.
– Factory had made some bad choices for wiring the heater and ac.

Heater works now as it was a pot that was trying to supply current to two relays at the same time.
– Only one relay would energize at a time and cause the heater element to smoke before the water pump was running.
– Now it turns on with a button.

The precharge board schematic looks to be finished.
– This will take the place of the precharge relay that does not last that long.

Heater temperature controller idea.
– Can use part of the precharge circuit to control heater temperature!
– Could run with any voltage EV heater up to 500 volts.
– PWM to the heater from zero to about 5 khz or so.
– Led and temp would be mounted on the dash.
– Opto isolated from dash.

The lithium cells were removed as I overcharged them and they now have a reduced capacity of 10%.
– When I can get a data cable fished from the box to the cabin, I will reinstall the lithium cells.
– 3 New 50ah Hi Power Lithium cells are due to arrive next week for evaluation.
– The good news is that the cells went many hundreds of miles without issue.

Lanny is putting some Lithium cells into one of his Rangers as we speak.
– http://southtownelanes.com/ranger_lifepo4.html
– NIMH Ranger hardware used for the BMS.
– Only monitors every 4th cell.
– 100ah pack of what looks like Hi Power cells (from Thunderstruck Motors).

Had some cells that appeared to be low on electrolyte only to discover they were just very undercharged.
– They spewed KOH and had to be removed and cleaned up with vinegar.

Pack was ground faulting during the last rain.
– 3 sides of the lid had new weather stripping. The 4th side that leaked had a different and softer material.
– The 4th side now has the better material like the other 3 sides.
– Also cheated by tweaking the software so the truck is not so sensitive to ground faults, until I get the battery box water tight.
– With 500 terminals, 5 times more than a lead acid pack, it’s easy to get a ground fault.

Nicad pack now has 12k miles on it as of this week.

The tilt bed on both trucks now has two gas struts per side.
– Makes lifting the bed easier.
– Holds bed up without a prop rod.
– Sometimes in the garage the bed needs to be held down. Prop cable?
– Can demonstrate outside.

The #2 truck has an unpainted roll pan that needs to be finished and installed.

Blog is http://rotordesign.com/blog

I’m down 38 lbs.

#1 Nicad truck
It rained!!
Had to add Rivet nuts to holes on sides of battery box to correct stripped threads.
Taped paper towels into each corner for use as water detector.
Replaced worn out weather seal with natural gum from McMaster.

-Lithium
Cells have 400+ miles on them.
Zero issues so far.
Ordering Hipower brand lithiums for testing as well.
Same format as Thundersky’s.
BMS needs to just be installed for monitoring cells.
Got interupted due to rain.
A multi conductor cable needs to be threaded from pack to cabin for data line.
BMS tested fine on bench.

#2 truck
Purchased in running condition with ruined pack.
Added 35ml of water to each of 6 cells, and charge cycled, to no avail on one EV-1 batt.
Needed Emeter heater and a/c fixed.
Emeter and Heater repaired.
Installed diesel truck block heater.
Factory defect in heater controls.
2700w heater element turns on before the water pump operates!!
Works great!!
Hinged bed works awesome!
Used Heim joints.
Added 2nd pair of gas struts to lift bed.
Bed lifts nicely.
Bed stays up easily without prop rod.
Plan to upgrade nicad truck with 2nd set of gas struts too.
Battery box needs nearly all holes helicoiled.
Added fuses to Dolphin to protect electronics.
Ordered tons of parts from GM.
Rollpan, antenna, blower switch, and cupholders.
Adding a blog to chronicle progress.

-Borrowed a board designed to replace the precharge relay on US Electricar vehicles.
Intend to reverse engineer and add to my vehicles.
Could be super reliable!!
Relay is $229.

-Dave’s Soleq wagon is running ok.
Regen is not working due to busted pot return spring.
But at least it’s driveable now.
He just bought a non running Solectria recently from Ebay.

-Home Power Magazine had an incredible article in their Oct/Nov 2008 issue that contains real test data on the cycle life of various brands of lead acid batteries!

-Bought a 240vac Variac for charging cells after a deep nicad cycling.

-The truck is 35lbs lighter because the driver lost 35lbs!

– Most parts for UK Lithium BMS arrived Thursday.
Resistors were too big at 1/2W. Should be 1/4W.
Some caps too big too.
Had to generate my own BOM since owner did not. Big pain!
Picked up correct parts from Halted.
Built 1 and mostly assembled the other 2 last night.
Completely open source.
BMS will have a 3.5″ lcd.
BMS needs to be updated from 1/4 amp of bypass to 2 amps.
Requires a heavier duty transistor that I have.
Will get BMS assembled over next few days.
Discovered this morning that the boards don’t fit the cell mounting holes!!!
Can machine them so they fit.

– 3 Thundersky cells installed in nicad pack.
Had to machine end plates to cover 6 screw heads.
Driven about 80 miles so far.
Cells running cool at 50-70 amp loads.
Only 100 amps bursts so far.
Thermal readings while driving match bench testing so far.
Started at -10ah.

– #2 USE truck is being purchased.
May add all Lithium pack with BMS and then resell.
Has Air Cond. that needs work.
Has Emeter that needs work.
Heater needs work.

– A solid state replacement board for the precharge relay was discovered.
Precharge relay expensive ($229)and has a short life.
Reverse engineering could provide info to make a board for current USE vehicles.
Uses 8 amp, 500v fets with Opto’s.
Will upgrade to newer 20 amp, 500v fets.

– Purchased another clamp meter from Halted for $25.
Just missing the battery door.

Nicads
– 2 weeks before Rally truck only had a 12 mile range.
– Drained pack, shorted only lowest 70 cells. Did it twice. Helped some.
– Finally read the nicad manual and found that it said drain and short the whole pack, so I did.
– Made shorting clips with bailing wire as a load resistor.
– It helped a lot!!! Pack finally has a 20-27 mile range.
– Rally was 20.5 miles.
– Used 4.4 kwh to get to Rally.
– Fantastic efficiency 200 wh/mi at 45 mph! Loaded with scooter and tools!

Took scooter to Rally. It worked great.
– Had to machine a new hub until 3AM! Shattered into 4 pieces.
– Titanium return spring bent!
– Steering out of trim.
– Standing long sure makes the feet sting!

Made a panel that automates some of the charge/discharge testing.
– Designed in Rhino3D
– CNC Machined
– Mounted Emeter and other parts.
– Still needs to be wired to load tester and charger.

Thundersky 40ah cells from Green E motors.
– Tested at 103-105% at 40 amp load.
– Next test is 60 amp load, then it goes into the truck!
– Plastic insulators need to be machined to keep screw heads from poking nicads.
– Also have K2 cylindrical cells from Allen to test.

Found a voltage monitor IC for a Lithium BMS.
– LTC2912 from Linear.
– Has over undervoltage and undervoltage outputs.
– OV and UV will trigger a buzzer or external LED with an opto.
– Will try to get samples from Linear and test.

Found a BMS that is like my design, but is for sale at Black-sheep.us.
– Ordered 3 of them.
– $34 each.
– Designed to fit 90ah cell. Will use cables to adapt to 40ah cells.
– May modify Black-sheep’s design with LTC 2912 so it can be used on any battery voltage.
– Simple analog interface to an LED or buzzer for under or over voltage notification.

Wednesday night drained pack.
– Shorted cells Thursday afternoon thru Friday morning.
– Pack took on 41.5 ah’s (14 kwh).
– Biggest recharge so far!

Friday night
– Found that low volume cells were very low on water. At least one is damaged.
– Lots of overcharging without checking water levels.
– 6 Replacements were installed so low water cells can be tested.
– Driver’s side of pack is watered.

Labview classes all of next week
– COuld help in making an automated multi cell battery tester.

Bring: Markers, shorting clips, orange hammer, Emeter panel, picture of Blacksheep BMS,

Brazil!
– Photo album will be on my website.

Thundersky Lithium cell testing thanks to Allen at Green E Motors!!!

1.5 sets of A123 cells in house.

My trip to Brazil!

Robogames last meeting.

Going to Brazil July 23-30.
– Combat Robotics contest.
– Maybe sight seeing.
– Got my shots.

Testing truck for difference is processor operation.
– Taking scope shots of charger fet pwm.
– Chris shooting his mouth off again.

Recurved temperature gauge so it actually moves upward when it gets warm.
– Always sits near zero.
– Can’t tell if there is any temerature change.
– Now the needle will swing 1/4″ for each temp change.

USE member making a new software interface for the Dolphin using Labview.
– Could disable a vehicle easily with a rookie owner.

Shipped last Dolphin board for the summer!! So the to do list looks like this:
– Make A123 Lithium module. All meterials in house. How to connect copper plate to 10mm copper stud???
– Bought another A123 Dewalt pack from Ebay. Slow shipping. Need one more to make 2 modules.
– make/find BMS for same. Could use Richard Hatfield’s BMS.
– Install A/C.
– Install Thundersky lithiums.
– Install Richard Hatfield’s BMS for Thundersky’s.
– write BMS talk for SVEAA Oct/Nov time frame.

Nicad Pack just hit 10k miles!!

Figured out that the Bar Graph BMS display will fit nicely in a machined rectangle in the dash gauge cluster.
– Machining of cluster face and lexan backing is easy due to being flat.
– Plenty of room behind cluster face for LCD mounting and cable interface.
– cables will leave cluster through slot machined in open area in back of cluster.
– Some software and hardware changes to make it universal for all USE owners.
– Only handles 18 batteries right now.
– Tim’s design will work, as designed, in my truck, but not in other owners vehicles.

Watched prices of Honda Insights on Ebay.
– 35k-45k miles = $16k-18k.
– >100k miles = $11k-12k.
– Some with Salvage titles.
– Santa Cruz Insight has a new battery but only a 12k warranty due to salvage title.
– Appears that salvage title kills battery warranty.
_ Do Insight batteries use welded tabs? compression? Soldering?

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