Arrow-7 or BBSHD

[galvatron1]

Looking for a safe 1st ebike. I've read ES stories of battery fires & have been hesitant. I can't charge in a garage, b/c I'm in an apt. Here are my 2 options I'm considering. Thanks.

Option 1
Arrow-7: http://www.flyebike.com/?portfolio=arrow-7
Speed: 30 MPH
Range: 50 Miles
Battery: 48V/20AH Panasonic Cells
Motor: 500W
Charging time: 6-8 Hrs

Option 2
BBSHD w/ Hailong-3 52v battery pack.

 

[MadRhino]

Almost all fire stories that you read, are with RC lipo. The chemistry is very aggressive and does require strict safety measures. The common ebike batteries are safe.

 

[Drunkskunk]

The Battery danger is real, but for a real ebike battery, it's not really more dangerous than a cell phone batter. Sure, those can burn, but it's rare and common sense will alleviate most of the risk.

Don't stab your battery with an ice pick and then leave it on top of a gas can.
Don't store your battery in the oven while baking cookies.
Don't leave it hooked up to the charger under the baby's bed on a bunch of flammable blankets.

As MadRhino said, most fires are from RC batteries. those are not meant for ebikes, and really should only be used by those who need the extreme high performance edge that a normal battery can't deliver.

 

[galvatron1]

1. How do ES members safely charge batteries in apts, when charging in a garage or outside your home is not an option?

2. Which seller's battery packs are built the best & offer the least risk of catching fire?

3. Are there any battery enclosures that offer some fire protection?

 

[spinningmagnets]

Buy a battery pack that is larger than you need, and can easily provide your desired amps without getting hot.

Charge at a slower rate, to keep the cells from getting hot. (I know its nice to charge fast in order to get it over-with, but...)

Charge to 4.1V per cell, instead of the common 4.2V per cell. By my calcs, you only lose 1/17th of the range, but you gain over double the life in months.

xxxxxxxxxxxxx

Cheap generic cells may have a manufacturing defect in one out of 1,000...fire risk.

If you get your pack hot, whether its charging, discharging on a ride, or just sitting in a garage in Arizona in July...it can damage the cells and make a fire more likely.

Cheap BMS or cheap charger: fire risk.

Charging to 4.2V per cell...how accurate is your charger? When it says 4.2V, is it really 4.25V?

 

[galvatron1]

Only charge to 80% when fast charging? What charger do you recommend?

 

[spinningmagnets]

Which charger?

I have a $99 Luna charger I'm happy with, the Satiator can charge at 80%/90% and has variable charge rate, and also...I am looking at the iCharger 3010 duo for a future project (no hands-on yet). With that unit, you can configure a DIY 14S pack as a 7S X 7S and balance-charge it to 4.1V per cell (no BMS).

I am sure there are also other options that work.

 

[d8veh]

Only charge to 80% when fast charging? What charger do you recommend?

Use the charger that comes with the bike or battery. You won't go wrong like that.

 

[galvatron1]

Thanks all! How are empowered cycles battery packs quality? I am considering their 52v pack, if ES members have had good experiences with this site: https://www.empoweredcycles.com/col...ts/new-hailong-3-52-volt-17-5-ah-panasonic-ga

 

[tomjasz]

Which charger?

I have a $99 Luna charger I'm happy with, the Satiator can charge at 80%/90% and has variable charge rate, and also...I am looking at the iCharger 3010 duo for a future project (no hands-on yet). With that unit, you can configure a DIY 14S pack as a 7S X 7S and balance-charge it to 4.1V per cell (no BMS).

I am sure there are also other options that work.

The satiator can charge at variable rates 50, 52, 81, 92, whatever nuanced level you want. I charge my welders 12v, kids scooter 24v, my 36, 48 and 52v and at those varied rates. Not a single battery voltage or lcked in rates with meh warrantees like so many others. I use a 1010b to work with mutiple loose cells.
Satiator remains best buy ever. So good i bought a second but a 72v (36-72).

 

[tomjasz]

Thanks all! How are empowered cycles battery packs quality? I am considering their 52v pack, if ES members have had good experiences with this site: https://www.empoweredcycles.com/col...ts/new-hailong-3-52-volt-17-5-ah-panasonic-ga

Matt is a top shelf reseller. Honest straight forward and fabulous support.

 

[cal3thousand]

There have also been a decent number of 18650 packs that have gone up in flames recently as well.

RC LiPo can suffer from poor QC, but once vetted, can be just as safe as other LiPo types. Poorly built and/or designed 18650 packs are just as likely, if not more likely to go up in catastrophe. Think about all the 'hoverboards' that have gone the way of ignition; they were all cheaply made 18650 LiPo packs.

'Common' ebike batteries are only as safe as the BMS, cells, pack design, and build quality. The issue with these packs is that many of the cheaper BMSes don't even come with a balancing circuit. Pair that with wild claims that lead the consumer to use their pack more aggressively than designed for, and bad things happen.

If you want a 'safe' chemistry, go with LiFePO4. It has it's obvious drawbacks in performance areas, but hands down safest common lithium type.

Once you're into LiPo, no matter if the cells were 18650s or pouches, the energy density and oxygen carrying chemistry create a risk.