Batteries vs Cold ☃

DrkAngel said:
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Right now it is about -10ºC = 14ºF, I've left my bike out in weather like this and it just does not run well.
Initial start-sag voltage from my 25.9V LiPo:
at 20ºC (68ºF) battery provides 27.3V
At -10ºC (14ºF) battery outputs a pitiful 23.4V
Yes! ... Cold is bad!

Bad for battery
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and

Bad for Bike:
All lubricant stiffens into a tar like substance that makes turning the pedals, crank, chain, hubs, derailleur like pulling taffy.
Brakes seem to engage in slow motion and when released, you can watch as the brake levers slowly return to normal position.
All of a sudden you want to put a pipe wrench on your shifter!
Even tires get stiff and make it seem like you are going up hill.

Keeping your bike inside-warm helps some,
but then your wheels hit the snow and pick up a nice layer of ice ...
not good for rim brakes!
and
Bikes get cold fast!

But!
YES!
I will be cycling this Winter!
Why? ... Hmmm ...
I guess I like the idea of triumphing over adversity ... ?
 
DrkAngel said:
Bad for Bike:
All lubricant stiffens into a tar like substance that makes turning the pedals, crank, chain, hubs, derailleur like pulling taffy.
Brakes seem to engage in slow motion and when released, you can watch as the brake levers slowly return to normal position.
All of a sudden you want to put a pipe wrench on your shifter!
Even tires get stiff and make it seem like you are going up hill.

Keeping your bike inside-warm helps some,
but then your wheels hit the snow and pick up a nice layer of ice ...
not good for rim brakes!
and
Bikes get cold fast!

But!
YES!
I will be cycling this Winter!
Why? ... Hmmm ...
I guess I like the idea of triumphing over adversity ... ?


You can change the lubricant to low-temperature-bearing-grease made of silicone :mrgreen:
What brakes act like this? my mechanical disc-brakes made never problems! Same for shifter! maybe you should drop some silicone oil in your shifter cable :D
There are special winter tires (studded and unstudded) for bicycle with softer rubber. :eek:
I like it too, no mosquito out there in the winter :mrgreen:
 
I've never had an issue other than chain rust from salty roads on my pedal bike. Certainly not with shifters or brakes! But I have hydraulic discs. What I want to know is if discharging at -10c temperatures is bad for the battery health, regardless of the resulting usable capacity.
 
xenodius said:
I've never had an issue other than chain rust from salty roads on my pedal bike. Certainly not with shifters or brakes! And I have hydraulic discs. What I want to know is if discharging at -10c temperatures is bad for the battery health, regardless of the resulting usable capacity.
Chain
For my chain, I use Finish Line "Wet" chain lube and heat the chain with a hair dryer till the thick lubricant flows into every crevice. I press a fine paintbrush against, while turning chain to coat all surfaces. This is the best method for Winter protection that I have found.

Cables
I, sadly, followed the manufacturers recommendation and coated all cables with lithium grease. Guess I will go back to using wax or paste wax, possibly heating cable and thinly coating with synthetic grease w/Teflon?

Cold Damages Lithium Battery?
Heat does damage Lithium batteries! There is a slight performance increase but a substantial deterioration of capacity and life cycles. All reasonable sources agree.
But there seems to be no authoritative info that cold directly damages batteries. ... ?
However ...
Deeply discharging battery greatly decreases the number of usable cycles!
At -10ºC (14ºF) available capacity is 50%, this means that a 50% partial cycle at normal temperature becomes a full depth "damaging" cycle at lower temps.
Logically then, cold is bad-damaging to the battery.

Other notes
Battery is damaged and capacity reduced by charging when hot or cold! "Room temperature" charging recommended!

Lithium batteries are best "stored" with a 50% charge (~3.9V - LiCo) at 32-40ºF.
 
Re the bike, I find that I generally have to make shock adjustments when the real cold sets in. Oil in the shocks gets thick, so preload or rebound adjustments may be needed. But if you have a cheap shock, you may not have much range of adjustment. I try to avoid using oils or greases on cables or chains. Mostly I use a white lightning lube. Getting water in cables sucks in the cold, since it will just freeze.

Re the batteries. I keep reading posts from folks who say their batteries are not affected by cold. I just suspect that their battery is perhaps not getting that cold.

When I first noticed cold affecting a battery, I was riding a bus part way to work on the coldest days. After the bike rode on the front of the bus for 10 miles getting wind chiled, it would be extremely sluggish and trip the bms a few times. After a block or so, the battery would warm itself up enough to work again. Fortunately, the bus ride shortened my ride enough to avoid a 100% discharge. I solved the problem by just driving to work on days that cold.
 
33.3V build is working nicely, too nicely, I got complacent.
Set my bike in the back storage area after my latest errand ride.
Usually I charge up the battery immediately after each ride, but ...

Just pushed it into the back room - storage area.
Storage area gets only partially heated, about a 30-40 degree rise above outside ambient ... it got down to -5 F last night.
So I took my frozen bike with partially discharged (70% full?) battery on a 5 mile commute at 0 F.
I had to pedal assist to maintain 14mph.
Typically, I can cruise motor only at near 20mph in similar circumstances!

So ... I learned my lesson ... again ... I will be meticulous about charging and storing my battery after every ride at my nice warm charging area next to the heater vent. Nearly 80 degrees F at tabletop charging level.

My old charging station was near the front door at floor level ... where Winter ambient was below 50F ...
Much better now!
 
I've been running my 24s 20ah A123 pack at 1-2c in -5C to -18C weather, stored outside, warmed up overnight then charged in the morning when emptied, for the last couple weeks. Performance suffers a bit, with the BMS cutting off at ~30 amps in the worst conditions, but otherwise it seems to be working quite well. Slowest top speed was ~30mph, normal top speed is ~47mph.
 
Just looked up specs for Molicell 18650 Li-ion. - got a few laptop packs worth ...
ICR-18650H
Made in Canada!

Well ... anyway found this temperature dependent discharge graph.

Cold Moli.jpg

This clearly demonstrates the horrific decline in performance from a cold battery.

Keep your battery warm!
 
DrkAngel said:
Just looked up specs for Molicell 18650 Li-ion. - got a few laptop packs worth ...
ICR-18650H
Made in Canada!

Well ... anyway found this temperature dependent discharge graph.

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This clearly demonstrates the horrific decline in performance from a cold battery.

Keep your battery warm!
21ºC = 70ºF and is considered the optimal temperature for charging and discharging most all battery types.

Storage temperature, on the other hand, is variously rated best near 0ºC = 32ºF to 5ºC = 40ºF
(@40% charged for LiCo) (@ 100% charged for SLA - recharge monthly)

Battery Storage Temperature

Storage.jpg

I intend on using my old re-re-recycled 33.3V 31.2Ah pack for the Winter.
Basement storage of my Summer batteries would be colder, but I am concerned about moisture-corrosion, so I will use partially heated rear store area instead.
(it stays above 40ºF but below 60ºF)


Yes, I will keep a "Summer bike" and pack, (with charger next to it), ready and waiting for warm weather.
 
I fly RC helicopters as my real hobby (expensive!!) and I definitely notice a difference in flight time and power when its told (less of both). Haven't noticed anything with my electric scooter but I haven't really driven it in the real cold yet.
 
Nothing to report for this Winter ... yet.
Warmest November on record in New York, USA.

Had a little snow that melted in a couple hours ...

Keeping battery warm (~65ºF) until ready to ride seems to eliminate the deleterious effects of cold weather, if you consider 40-50ºF cold ...
Bike and motor being cold seem to not have much negative effect ... so far.

Snow Beast is ready, geared lower and built a 33.3V 31.2Ah 18650 pack and plan on a 33.3V LiPo & RC LiPo Hybrid build.
Decided to go lower voltage (down from 37V) and higher amps (20.8A upgraded to 31.2A) to combat cold induced higher IR (Internal resistance.)
 
Global Warming?
El Nino?
Climate Change?
Where's the cold!!!

Upstate NY, USA - Report
2015 officially warmest year on record
Buffalo, NY ("The Blizzard Capital") record latest date for 1st snow ... still waiting!

Mid December - Olean, NY:
Dusting of snow on ~2 separate mornings so far
10 days before days begin getting longer
City sent out mowing crews to cut grass in the parks
Forecast is 60'sºF this weekend (lows in the 50's)

Update 12/11/15 - Philadelphia, PA USA
Cherry trees blossoming! - due to warm weather.

Update 12/24/15 - Christmas Eve day 12:12am 58ºF
50's through the weekend.
Still haven't had any snow that stuck more than a few hours ... in upstate NY USA.
Days are getting longer now, no snow cover to reflect suns warmth so ground soaks it up developing something of a high pressure system, which tends to keep jet stream and cold weather north of us.
After last years prolonged bitter cold ... seems nice.

Good chance I'll hit 7000 miles on 2008 eZip Trailz "Commuter" and 6000 miles on 2013 "Comfort Cruiser this weekend.
Haven't had any reason to break out the 2008 MT "Snow Beast" ... yet.
 
Setting-charging my battery at floor level <60ºF noticeably reduces performance compared to 70ºF Summer temp!

Chance of snow in Upstate NY USA? Maybe next year - 2016!
 
I ride for up to 4 hours at a time in -25 to -30C weather. Here's my findings.
Naked LiPo's stay above 0C for about 20 minutes.
Black insulation sheet wrapped all around keeps them above 0C for about an hour.
Two layers of black insulation sheet with a layer of E-tape all around will keep Lipo's above 0C for 2 hours!
Put in a cardboard box, and the box being given a layer of E-tape (Increasing thickness of the pack by about 3/4") the pack will stay warm for 3.5 hours!
All these things add so much air pockets and seperation and shielding from the wind...
Throw one of those handwarmers (The kind you can boil to reset and only last 15 minutes) into the box and close up the flap again. Do this after 2 hours and the pack will stay above 0C for almost 4 hours! All the heat stays inside-If you shoot it with one of those FLIR guns, the outside is at outside temps but when you open the box the whole damn thing is red, and it'll stay that way for a while if you store it indoors instead of parking it outside.
The ultimate solution are pack heaters. A member linked some 12v handlebar heaters, but the ultimate?
http://www.ebay.ca/itm/48V-Heated-Grip-Kit-Pads-Handlebars-for-Electric-Scooter-Bike-E-BIKE-2X10W/171483508409?_trksid=p2050601.c100085.m2372&_trkparms=aid%3D111001%26algo%3DREC.SEED%26ao%3D1%26asc%3D20140211132617%26meid%3D2abea89e766a4305af025479e8d3f9b1%26pid%3D100085%26rk%3D1%26rkt%3D4%26sd%3D171483508409%26clkid%3D2243542844363528643&_qi=RTM2247625
Two of these spliced into the controller's power feed in parallel and dump the heaters in the middle of the pack. This will keep the battery, with afforementioned insulation, warm indefinitely as long as the battery lasts. I left it outside with the heaters on for 8 hours during a work day once and the thermometer read 15C inside the pack. Magic. No modding required (TAPE OVER THE EXPOSED BRASS FIRST)

My bike:
Custom frame with a 50A shunt mod, 2kw
x6DIpiBm.jpg
 
Heat\Cool Thermostat-Control - (12V ≤10A)
Programmable from -50ºC to +110ºC.


Found up a nice budget thermostat control for heating pad or cooling fan.
I ordered LED and dip switch versions. Will post review after received.


- <$3 delivered

the 12V heating pads. - ≥$2.67/pair
 

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Been in the 30s for a couple weeks now.
But still have to keep reminding myself not to leave my battery outside on the bike.

Got spoiled!
Was in the 70s right till mid-November.
Now, unless I keep my battery warm, it will sag into the red under full acceleration, in 80 degree weather that usually won"t happen till after 20 miles.
Even moderate temperatures show noticeable voltage sag.
(3 year old 25.9V 25.92 recycled Laptop LiPo packs with ~6000 miles on each)
60ºF battery, at floor level is a marked performance decrease compared the 70-80ºF battery of a few weeks ago.

Seriously considering an elevated charging-warming station near a heating vent.
Will monitor temperature to determine advisability.
70ºF is generally accepted as the optimal charging and use temperature for most Lithiums.
 
Getting my Snow Beast ready.
An eZip with studded tires, upgraded with 37V for extra umph through the snow. (23mph with summer tires)
37V Homemade recycled Lithium packs all worn out.

So, decided to convert for my 33.3V batteries.
Have 33.3V 43.2Ah LiPo in insulated 6pack cooler and 33.3V 31.2Ah recycled 18650 LiCo in oem eZip battery pack.

Problem is ...
When it gets cold, 33.3V battery sags to 36V controllers 31V LVC way too soon!
So ... will replace 36V controller with one of the cheap 24-36V+ capable controllers I found.
Of course, without a reasonable LVC, I will monitor battery voltage with a handlebar mounted volt meter.
 
Discharging in the cold is a major issue the grunt is not there the electrons don't seem to be as free to move in the battery, Charging is another issue if the cell is colder than the 72F around 50F or under then the capacity will fall short by 10% or more at charge then a cold discharge on top and it can fall weigh short of capacity.

I have used aluminium plates on my lipos to cool them and in the cold 32F the discharge was appalling barely half capacity and lv dropout when over 3c (10c rated) thats over 0.8v drop per cell, I could not get any heat into the cells it was dissipated through my heatsink so I could never get over 70% of my performance and I think this figure is only this high because my pack is overrated discharge wise and my ride pulls 56amp at 16s so the lipos can keep that up no sweat in the summer.

Its got me thinking that what low discharge lipo cells need is not hardcore cooling but temp management a way of keeping the 70F sweet spot, I've heard a few good ideas from different sources on here and I'm stitching it together, I've got my new 20s 10ah turnigy graphene pack build so I'll be using polycarb to contain all the cells, I will never use more than 1/3rd the c rating to limit heat gathering, ill give plenty of room around the cells so its not one fat stack of lipo, keep it enclosed with a controlled airflow on a thermostat so I can maintain closer to 70F
 
DrkAngel said:
Rig up the heat pads to a nice little programmable thermostat, and keep your batts nice & warm.
LCD programmable 12V thermostat - $15.99 w/shipping

Note: "Current on Relay Contact AC 5/220" ... Relay Contact should work fine at 12V DC! - AC-DC any voltage - 5A/220V max!

be nice to use when leaving the battery with the bike in a cold area to have a nice warm battery every morning juiced to the nines.

When I build a pack I will add mini heat strip system for it as a custom touch that may well extend its cycle life as well as maintain the AH rating.
 
Just left my new HO Samsung cell, (10A per cell continuous) build, all day in 30-40ºF temperature.
Took a run about 6pm and cruised at my typical 20-21mph.
Battery seemed to perform at very near 70ºF capability!
But cruising at only about .7C.
Will update when temperature drops another 20 degrees.
 
DrkAngel said:
Just left my new HO Samsung cell build, all day in 30-40ºF temperature. (4.5-9C 10A per cell continuous 20A surge)
Took a run about 6pm and cruised at my typical 20-21mph.
Battery seemed to perform at very near 70ºF capability!
But cruising at only about .7C.
Will update when temperature drops another 20 degrees.
Should have noted:
Similar capacity LO (1-2C) Laptop LiPo build sags horribly in similar conditions!
15-16mph capability when battery at similar temperatures.
 
This years upgrade for winter travel.

Screen Shot 2017-11-29 at 12.02.01 AM.png
 
5V USB Heating Pad For Electric Heating Carbon
8W = 1 x 2200mAh 18650/hour
40-45ºC = 105-115ºF

 
Was looking on ebay for heated grips and ended up buying two sets they seemed so useful and cheap at $4 each

I assume its a heat shrink plastic sleeve
s-l1600.jpg


Voltage options are from 12v to 72v

s-l1600.jpg


My battery uses this connection so it can be plugged and unplugged as needed. Will likely wire the other set from the controller end to use on a set of clip on aerobars

S2064075-5.jpg
 
DrkAngel said:
5V USB Heating Pad For Electric Heating Carbon
8W = 1 x 2200mAh 18650/hour
40-45ºC = 105-115ºF

The long thin wires are best replaced or they carry as much heat as the pads. There are some diy “carbon fiber heat pads” on aliexpress, small but $1.35 each.
 
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