Charging ebike in the boonies

[muttmaster]

Not at all Vic. You have helped me so much in the past. From upgrading to heavy gauge cable from truck battery to installing Trimetric in my older camper, etc. you’ve been a great help. Convinced me to get a Victron 100/30 that should be in my mail today.

By the way. As many times as I have seen you recommending Victron, you must be getting a cut from them right? At least you should.

Just got a book “DIY Lithium Battery”, hope I learn something before my ebike arrives.

 

[Vic Harder]

Thanks... much appreciated.

No cut, no affiliation. Nor with PKYS.com. Both are excellent though.

 

[buckland]

Old Crow Thanks for that video. I have a DIY ebike (52V 20 Ah). I found the thread interesting as I too wanted to charge from Camper battery set up using a 1000 W inverter. I bought a second Battleborn (to be put in parallel). Hope this will work and will find out when the snow melts!

 

[Old Crow]

Looking forward to seeing what you learn, buckland!

 

[Jack]

I will try. Getting many post on best way to juice up.

I watch few Utube video on DIY Lithium. 280 ah with four cells plus BMS for $500 or so China. What do you think? I like to just use battery charger provide by Radbike and even charge two battery over night. I will have plenty of ah left in the AM.
My two AGM in Grandby is five years old now, doing fine, but planning on getting more juice.

I went the DIY route. If you are comfortable with electricity, it's not particularly difficult. See https://www.wanderthewest.com/forum/topic/20568-new-lithium-battery-%E2%80%93-some-assembly-required/?hl=lifepo4

 

[muttmaster]

Thanks Jack for your DIY battery link! Awesome. I watched few Utube intro on builds and just got a book on DIY.

Did you get a Victron Smart Sensor. I understand that it can be set to turnoff charging at programmed temperature via Bluetooth. If that is that is the case, I won’t have to deal with heaters, etc. I camp in Winter a bit and don’t want cause damage charging at low temp.

Your battery cell ordered from Alibaba I assume? Vendor. I should read your DIY post first before asking.

 

[Jack]

I updated my build post with links to Alibaba and the other vendors: https://www.wanderthewest.com/forum/topic/20568-new-lithium-battery-%E2%80%93-some-assembly-required/?hl=lifepo4

The BMS has a temperature sensor that I wedged between two of the cells and the BMS will prevent charging below 32F. There's also a high temperature shutoff (113F?) but that won't be relevant in VT, at least for a while. You can change these limits in the BMS settings, and rando has a number of posts on charging at lower temperatures. Essentially, lower charge currents let you charge at lower temperatures. You can control the charge current in the Victron MPPT. The Victron DC-DC does not let you control charge current (but Victron says maybe in the future via an over the air update). If you disable the MPPT (via Bluetooth) and you charge only from the DC-DC, you are limited to a bit over 30A charge into a 280Ah battery. That's a charge level of about 0.1C - 10% of battery capacity. If the engine is not running, then the MPPT can charge no more than 30A or less if you change it via Bluetooth.

I have the Victron Smart Sensor. The Victron MPPT uses it to source the right voltage such that the voltage at the battery is the correct charge voltage. There is no "voltage drop" issue. Unfortunately, that is also a future upgrade to the Victron DC-DC.

 

[muttmaster]

Jack,
I bow before you. Thank so much. Just got notice that my Ebike is arriving on Monday! I thought I had a few weeks. I better place order today!

 

[muttmaster]

My new Ebike arrived yesterday, weeks earlier than initial delivery date. Maybe they had a fast boat from China. Did my first of three recommended balancing charge with 350 watts pure sine wave inverter. My first ride was to run down the battery level to about %25, and had no problem charging with stock 75ah AGM in the camper. I guess I worry too much.
I did order LifePo 200ah cells and will built battery to replace the aging AGM. Got a 800 watts inverter coming too as I anticipated charging two Ebike batteries at the same time.
Thanks all for your inputs and inspirations. I will continue to experiment with charging in the boonies and see how my system can handle my needs. I will update as I go along.

 

[buckland]

Thought I'd come back and ask more questions! As a reminder I converted my mountain bike to e-bike. It is wonderful. Attached is the battery and charger info. The battery is 52 V 11.6 AH and the charger is 52V 3 Amp. I have in parallel 2 Battle Born batteries for a total of 200 Ah. I have the 1000W Renogy pure Sine Wave 12V Inverter. The inverter is connected directly to the BB battery with heavy gauge 2 ft cables. ( the inverter in not independently grounded to camper frame other than through battery)

I ran the e-bike battery pretty close to empty and plugged in the charger to e-bike battery then plugged the charger to inverter then turned on the inverter.

Immediate chirp from inverter.... then it starts 15 seconds .... then the fan turns on as the 'fault' red-light comes on and the alarm and I believe it has stopped the charge.

I immediately turn off inverter and wait... then retry with same results.

Charger works fine on 110V in garage. I assumed (?!) the inverter could handle this load. My BB batteries are at 14.2 V 200 Ah.

What am I missing?

 

[Vic Harder]

What happens if you turn on the inverter with no loads plugged in?

 

[buckland]

Hello Vic! Just went out and tried. Turn on ... a beep (red light too) for 1/2 a second .... hear the fan... then quiet with the green light on.

 

[Vic Harder]

Try a different load?

 

[buckland]

I will plug in an electric fan tomorrow... having a beer now at 8PM is not a good time to play with electrics!
Not knowing a lot about inverters.... in campers... should it be grounded additionally other than through the battery...and is that the reason perhaps for the alarm went off? actually Vic... you have an induction plate stove burner which must pull a lot of amps real fast .... so is this any different from a charger?

 

[Vic Harder]

I will plug in an electric fan tomorrow... having a beer now at 8PM is not a good time to play with electrics!
Not knowing a lot about inverters.... in campers... should it be grounded additionally other than through the battery...and is that the reason perhaps for the alarm went off? actually Vic... you have an induction plate stove burner which must pull a lot of amps real fast .... so is this any different from a charger?

My inverter (AIMS 3000W) does not need an additional ground. The Induction cooktop pulls 1800W (150A or so) and does it happily. Something funny is going on in your scenario, and I'm just telling you to try a few things I would try if I was sharing a beer or 3 with you. Your ebike charger should work just fine....

 

[buckland]

I tried the fan and it works fine.... perhaps the draw from the charger, when first started "jumps" to too high a demand? (not really electrical lingo) and if so... is there a "capacitor' that could cushion the initial shock that trips it off?

 

[rando]

I am guessing the bike charger has a large capacitor on the input, which is causing the issue. When you plug it in, the capacitor on the charger tries to charge (they charge almost instantly) causing a large in rush current, that trips the inverter.

There are a couple of things you could try - to see if this is the problem, plug the charger into line power without the battery and let it sit for a minute (maybe plug the camper into shore power and use the inside outlet on the camper). This will charge the internal capacitors. Then quickly move the charger to the inverter - if the inverter stays on then it is capacitive in rush that is killing it.

You may be able to solve this by trying to turn the charger on several times in quick succession. While the inverter will shutdown the first couple of times, it may be providing enough power to at least partially charge the capacitor before it shuts down - on the third or fourth try it may work.

An electrical way to solve this would be to use an inrush limiting device.

 

[buckland]

1....... I wish I had your knowledge and experience (the good stuff!) ...... I was on hold forever trying to get the tech help from Battery charger as Volts and amps are on the back but not wattage... this info was asked at Renogy. I have recharged the battery (in the house) so I have to go for another ride tomorrow to drain the battery a bit then I will try the idea of plugging in via the shore power and switching over..... wondering does that then set the capacitors or must I do that each time?!

Attached is the e-bike battery 'specs' .... it says 603 Wh ?
If I do have to install the inrush device .... I think it is way above my skillset though maybe I can find some to do it.
Could it be the 1000 watt Renogy is to small....

Seems I am always dancing on thin ice with electronics so thanks for the advice

Also....Vic... love to lift a jar of suds one day after all this crazy coodies goes away...

 

[Vic Harder]

Your Renogy should be up to the task. I had one before I bought my AIMS. It could handle a bit of inrush, but not the full load of my induction cooktop. A battery charger should be an easy load.... rando may be onto something - he is a very smart fellow indeed!

As for the caps "setting" you would have to do that every time. It would be interesting to plug in the charger after the inverter is already on, and with no battery to connected. And THEN add the battery load. There will be sparks, so don't do that around combustibles.

 

[buckland]

Went for a good 10 mile ride and really cheated by not pedaling! (for scientific reasons of course) wanted to drain down the battery as much as possible so I could test the ideas stated above. Alas... though the charger rain for 10 seconds instead of two it still overloaded. I had plugged the charger into the inverter then turned on the switch (bike battery not connected) waited 20 minutes...then with the charger still on... plugged it into the battery.

Was now wondering if there is a "Inrush limiting device" rando mentioned above that is incorporated in a male/female adapter that I could plug inline to the inverter...then the charger into it. Can one be made...or do the "Inrush limiting device" (capacitors) need be soldered into the charger?