Electric Bike Battery Charging, options and advice

klahanie

Senior Member
Joined
Nov 23, 2007
Messages
932
Location
SW BC
have used foot notes (*#) for detail, thx ...

So, we have purchased two electric bikes to take along on our trips. Now I'm seeking advice here on how we might charge the bike batteries ("BB's") while on the road.

For most anticipated bike use (touristy ride in the park, around town stuff) I think we'll be able to rely on charging while driving. However with these bikes I see us doing some targeted rides, at least for the first 2 years, where we would stationery camp for 3 nights (camp, day ride, camp, day ride, camp).

My thought is to charge the BBs at night, after the day's ride, using the inverter and house batteries. If the next day has nice weather we will be riding and wanting full BBs. If the weather is lousy we'll prob be driving, rolling on to another place, charging as we drive.*1.

It's pretty easy for me to come up with a working number of ~62Ahrs of use. *2. Question is, how do we replace that, charging the house batteries during the second day while we are riding ...

Solar:
~600+USD. Don't have it. Initially was thinking a small suitcase set up that could be carried forward to a future rig. Read up a bit, now think we'd need 250-300w panels min, maybe 36v, complete with mppt charger. Summer time use, north of 49* latitude, some of these rides will be on the west coast beaches (could be foggy even in August). Lots of variables. I don't know what to expect for a day's total charge ??

Generator:
~200-800USD. inverter generator. Don't have it nor really want it but could make a case for one because live in an earthquake zone. Don't want a 2000w - too big to carry. That means 1000w which is small for home back up. Could be cheap and turnkey but could/would I leave it running while away riding ??

House battery addition:
~100USD. Already have 4 house + 2 truck. Could add 1 more battery, a cheap one. Would want separation ability. Bit of wiring involved. Kinda oddball.

Bike Battery addition:
~500USD. Buy a spare BB. Works with both bikes, giving us 50% more range, maybe give us 2 days travel. Redundancy. Still need to charge them. Wait a year and the market might have higher capacity BB at same price ??

Human power:
Do nothing. If run out of juice then pedal manually. Cheapest and easiest. Some of these trips will be remote, some with tide considerations, might be 15+ miles in/out. These bikes are heavy (60+ lbs), if we have to push them that will suck !!

Sorry this got long, thanks for reading.
What to do ? Comments welcome !


*1. Our rig has no solar or generator but has a fairly robust alternator charging system with heavy ga wiring to 2 x ~200Ah battery banks, a 2000w inverter and a 45 amp house battery charger. We rarely camp more than an overnight.

*2. The BBs are Lithium-Ion rated as 11.6Ah at 48v, so 555 watt hours, and are normally charged with a 120vAC 2A charger, reportedly for up to 5.5 hours. If we use a bit more than 1/2 battery capacity per day ride x 2 bikes we'd use ~600 watt hours or 50Ah at 12v. -- if I have this conversion correct -- Add another say 25% for losses inverting to 120vAC then converting to 54vDC for BB charging and we're at ~62Ah required for replacement (!).
 
You may be able to get by with just an extra house battery (~$150) for your "camp, day ride, camp, day ride, camp" scenario. Assume you charge the batteries on the way to the 1st night of camping (or at home), you then have capacity for day 1 already in the batteries. You recharge your batteries from your second house battery on the second night of camping (depleting the house battery in the process) then you ride on day 2. You would need to drive on day 3 in order to charge both the house battery and bike batteries, but you could help this out with a small solar setup (~$250 for 100 - 150W portable kit).
 
I'm with rando... a portable solar panel may be all you need; however, the far wet coast could make that totally useless. For folks who haven't been to Vancouver Island, think SanFran on a really foggy day.

klahanie, how many AH in that combo house/truck battery bank? Are you monitoring your existing battery status after a day or two of not driving? I'm trying to gauge your current reserve AH amount. Maybe you can suck out another 62AH without any concerns!

The charging system you have in place for recharging while driving sounds great, and similar to mine. It would be best/simplist if you could keep using that. For example, I can recharge 62AH in just 1 or two hours of driving. How far/long do you drive between camps?

The Stiriling units would be a good way to get 48V out of your 12V battery bank(s).
 
Lighthawk, nice ! I didn't shop that model but now see that step thru design would have been a big plus for me. Beefy rack also. Thanks for the Sterling tip. Is it this one ? I'll look thru later ...

http://www.sterling-power-usa.com/library/ProCharge-B%20IP68%20B2B%20owners%20manual.pdf
---
rando, yes you got it. I'd be happier spending $250 on solar than a full system for this camper. Portable has potential for other uses too. Will consider, thanks
---
vic, so you've been to Tofino in Fogust, eh? 2 battery banks, each ~200Ah. Second bank was for a goofy reason, will need to rework things a bit but agree I might (should) have enough for 62Ah. It's just I like to have a reserve. Yes, with 2 alts and 320 amps (?) and 0/2 wiring (don't ask) I should be able to charge quickly but have no monitoring. Likewise with usage, beyond the inverter's low voltage warning beep. Realise some info could be useful going forward. If you wouldn't mind repeating yourself, do you have a monitor recommendation for a thrifty fellow ? Thanks

~David
 
^ Thanks for that, Vic.

With a little more reading it seems this Lithium-ion bike battery doesn't need to be recharged as soon as possible. I had been thinking two overnight charges of ~62Ah rather than one. So now might be okay with my present house reserve.

Also, apparently this battery type should be long term stored at less than full charge, which would explain why I was told by seller it is supplied at 80% full.

for those following, here is a 120v smart charger I came across. It features adjustable charge per cent and speed.
https://lunacycle.com/batteries/chargers/luna-charger-48v-advanced-300w-ebike-charger/
 
klahanie said:
Also, apparently this battery type should be long term stored at less than full charge, which would explain why I was told by seller it is supplied at 80% full.
My last couple of laptops with lithium batteries have automatically opted to maintain charge at 50% if normally used while plugged into AC power. When it switches to optimize battery health from optimizing run time, it discharges until it reaches 50% then maintains that percentage.

Paul
 
Weather has been crappy forever but I'll throw in a few pics here of a recent ride for anyone following ...

lrpChng.jpg


Just a stream crossing. Yep rains a lot here.
R4SKukv.jpg


Gwh1yvK.jpg


Very steep at this spot where fabric has been added to surface, this coming up from the saltchuck (next pic). Fortunately these bikes have a "push" assist so you can walk alongside while under reduced power.
NB2lI93.jpg


bDF1SJl.jpg


Anyhoo, that's the idea. So far so good, think these will be a great add on to our road trips.Would definitely get something like this if I was bike commuting, but lose the balloon tires. 'Course if they get too popular they'll ban them.

Still getting a handle on power usage...

EDIT for pics
 
Beautiful trails! Thanks for the stoke.

"I don't know what to expect for a day's total charge ??"

I got my new Genasun boost controller wired up yesterday on my cargo bike. The panel is a 100W Renogy flexible monocrystalline. The battery is 48V 17.5 Ah. Yesterday was partly cloudy. I am in Eastern WA. At 1:00 PM, the battery started off at 65% charged. Four hours later, it reached 88% charged. The input current to the charge controller was hovering around 3.5 A. That was better than I expected.

My current battery- Luna Cycle Jumbo Shark battery- has a BMS that will not allow charging while under load. The battery switch must be turned off I think. It did charge for a while with the switch on, but then seemed to stall. I have a new AllCell battery on the way. Their engineer confirmed I can charge and ride at the same time with their BMS.

Very pleased.
 
^ Good info and lead, thanks husky.

17.5 Ah what kind of range you figure ?

Lucky you with partly cloudy, here it is plain old steady rain :( but your reply did get me out, so won't complain ... :)

HJr5GJr.jpg


KIh0ljp.jpg


Charge and ride, eh ?, WOO HOO !

Where will you put the panel ?
 
I get about 40 miles before I start to get low voltage cutoff from the motor controller. If I may post an image on your thread ...

TnHuSDS.jpg
 
^ friggin awesome !!

love the engineering. the upper seat tube bracket/panel holder is a thing of beauty and the motor, guess the eastern slopes should be no prob now !

Thanks much for sharing.
 
Came across this battery charging safe - an ammo can - and it got me thinking.
Battery safe:
https://lunacycle.com/luna-charge-safe-lithium-battery-storage-box/

The battery pack for our ebikes are built from Samsung INR18650-3G which are prob very safe but I was planning on charging them overnight inside the cab or camper and now, on reflection, wonder if charging them outside would be a better idea especially if we are sleeping at the time.

I think maybe a smaller 40mm ammo box would fit 2 batts but there wouldn't be much clearance inside. Would cut some holes for power plug and ventilation.

iu


Was thinking about using an an outlet timer as well to limit the the power on time.

Any thoughts on having one of these outside overnight with a couple power cords attached ? Actually maybe two boxes, the second being for the chargers - thinking charger and batt should be separated ? Or is this all over the top ?

Thanks,
 

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