Opportunity charging of Headway 9Ah LifePo4 pack

[imorton]

Hi Guys, I want to thank everyone for all the helpful info that I have received here. I am now contemplating buying the 48v 9Ah headway LifePo4 battery pack from BMSBattery.com As my budget is limited, I figure I get get this pack with a 6amp charger and shipping included for @ $400. I chatted with BMSbattery and they say these are B Grade cells and have @ Impedance: ≤5mΩ where the 10Ah cells are ≤4mΩ. What are your thoughts on this?

http://www.bmsbattery.com/packs/559-48v-10ah-38120-lifepo4-battery-16-cells-ebike-battery-pack.html

Since my scooter is @ 150 lbs, I weigh 240 lbs, and it has a 350w/500w peak motor, and a 17 amp controller and does @ 32 kph, while pulling 11-13 amps on flat land. I may, and may not do a controller mod to up the current to 25 amps, but I'm not sure. Like you all now, I can drive it slow and pull @ 6-8 amps on flat land while doing 20-22 kph, but it does get boring, so being able to run wide open (loll) would be much more fun and quicker.

I am thinking of getting the 400w LifePo4 battery charger (48v 6amp) so that I could quickly recharge the battery via "opportunity charging". I also have a 2a SLA charger for use at home were time is not an issue. What are your thoughts on this?

My thoughts are since my distance needs are generally small, @ 10-20 kms, the 9Ah pack would serve me well and save a fair amount of weight. NOW, if I needed to travel a further distance, I could recharge my battery within 60-90 mins by using opportunity charging by removing the small battery pack and charging inside a restaurant, coffee shop, or library etc….?

I find that there a very few places where I can charge my scooter outdoors, yet by using a removable battery pack, the recharging points are almost endless as I could remove the small pack and put in a discreet bag and charge indoors, like coffee shop, dentist, restaurant, library, etc… What are you thoughts, good or bad on this?

Does anyone have any experience on this 48v 9Ah headway cell LifePo4 pack from BMSbattery? They are apparently B Grade cells, but from my research, B grade doesn't necessarily mean bad, just not exactly to original specs. Any thoughts ?

I figure that if I "half" the life cycles, I could get 750-1000 cycles by using 80% Dod, and since I use 3 cycles a week, that would last me 5 or more years, and by than, "calendar life" will become an issue. What do you think of this?

Thanks for your help as there are so many variables… IAN…

 

[dogman dan]

B grade would scare me off. But B grade headway may still be better than A grade of other lifepo4 cells.

I totally understand the reluctance to go with something like a 48v 15 ah pingbattery. It's a LOT of money, especially if you don't run 25 miles a day or more. With the headways, a 10 ah size should be big enough.

 

[imorton]

B grade would scare me off. But B grade headway may still be better than A grade of other lifepo4 cells.

I totally understand the reluctance to go with something like a 48v 15 ah pingbattery. It's a LOT of money, especially if you don't run 25 miles a day or more. With the headways, a 10 ah size should be big enough.

I researched a little on the A-B-C Grade cells, and apparently it has nothing to do with cell quality. It appears that it is a way to classify the cell capacity and cell specs for the consumer market.

If I was to buy a headway pack, I would definitely order two spare cells in order to have on-hand should a cell become bad. That's would frightens me about Li-Ion packs, should, if, or when a cell goes bad, basically my pack would be toast/garbage. At least with the Headways, I could basically swap a cell.

I'm not sure that a 9Ah for $224 versus a 10Ah for $278, if 1Ah for $55 dollars is worth it? Unless there is substantial difference between A grade versus B grade?

Hmmmm, so many variables, decisions, decisions, decisions…

 

[imorton]

Does anyone remove their battery packs and recharge them INDOORS like in a coffee shop, library, dentist, etc…?

What are your reactions and issues with this? Are people or restaurants suspicious , or are people more involved in their phone/laptops/meals…?

Does a 400w 48v8amp BMSBattery charger make a lot of noise when charging, especially since it will be in a open recyclable grocery bag?

IAN…

 

[imorton]

Does anyone remove their scooter/ebike battery and use a powerful charger to charge indoors in a restaurant or coffee shop etc….?

IAN…

 

[teklektik]

I am now contemplating buying the 48v 9Ah headway LifePo4 battery pack from BMSBattery.com
...
Since my scooter ... has a 350w/500w peak motor, and a 17 amp controller and does @ 32 kph, while pulling 11-13 amps on flat land. I may, and may not do a controller mod to up the current to 25 amps, but I'm not sure. Like you all now, I can drive it slow and pull @ 6-8 amps on flat land while doing 20-22 kph,...
What are your thoughts on this?

So - figuring 13A at 48v and 32kph we get 19.5 Wh/km. Figuring 8A and 22kph we get 17.5 Wh/km.

Here's a couple of snippets from a mileage calculator showing the range difference between 10Ah and 9Ah cells assuming 80% DOD.
(The spreadsheet was set up for Wh/mi but just assume Wh/km...)


The 25Wh/km figure is likely where you will end up with a little headwind or if you upgrade your controller. Also, the cells will not put out this same power in the cold or towards the rated lifecycle limit when the capacity/range will drop.

I think that the $25 savings for the grade B cells may not be the best choice. You are certainly safe for 10km runs, but maybe not so much for the 20km trips. Anyhow, you can make of this what you will, but I would hold off for another $25 and 10% greater range.

 

[imorton]

I am now contemplating buying the 48v 9Ah headway LifePo4 battery pack from BMSBattery.com
...
Since my scooter ... has a 350w/500w peak motor, and a 17 amp controller and does @ 32 kph, while pulling 11-13 amps on flat land. I may, and may not do a controller mod to up the current to 25 amps, but I'm not sure. Like you all now, I can drive it slow and pull @ 6-8 amps on flat land while doing 20-22 kph,...
What are your thoughts on this?

So - figuring 13A at 48v and 32kph we get 19.5 Wh/km. Figuring 8A and 22kph we get 17.5 Wh/km.

Here's a couple of snippets from a mileage calculator showing the range difference between 10Ah and 9Ah cells assuming 80% DOD.
(The spreadsheet was set up for Wh/mi but just assume Wh/km...)


The 25Wh/km figure is likely where you will end up with a little headwind or if you upgrade your controller. Also, the cells will not put out this same power in the cold or towards the rated lifecycle limit when the capacity/range will drop.

I think that the $25 savings for the grade B cells may not be the best choice. You are certainly safe for 10km runs, but maybe not so much for the 20km trips. Anyhow, you can make of this what you will, but I would hold off for another $25 and 10% greater range.

Thanks for the reply… I apparently not receiving my "notifications" for these posts..

Interesting spreadsheet to calculate the range for different size batteries. From what I see, a 9 or 10Ah Headway pack will easily cover "my range needs", and I should ask Santa to get me a 20Ah pack instead.. loll

What I like about the 9 or 10Ah Headway pack with a 6amp charger, is that I could easily take it out of the scooter and throw it into a portable bag and "recharge it" indoors at a coffee shop etc… (should I occasionaly need more range)

I just wonder how loud these BMSbattery 6amp battery chargers are? Would people be disturbed by charging the Headway pack in a coffee shop?

Thanks for all your replies… IAN.

 

[dogman dan]

Depends on what you call loud. As a construction worker, loud is a nail gun to me. But the old lady in the next booth with perfect hearing thinks butterflies flap their wings too loud. The fan will make a definitely noticeable whirring sound on any 5-6 amp charger. Some smaller chargers, like 2 amps, have no fan. But that would take a long time.

For a very short visit, it might be possible to disable the fan and get 20 min of charge without frying the charger. Or not.

Some have been using sealed power supplies for bulk charging. See a thread in this section with LED power supply in the title. Perhaps you could use one of these more rugged, and silent power supplies for your opportunity charging. Then leave the fan cooled unit at home.

 

[imorton]

Depends on what you call loud. As a construction worker, loud is a nail gun to me. But the old lady in the next booth with perfect hearing thinks butterflies flap their wings too loud. The fan will make a definitely noticeable whirring sound on any 5-6 amp charger. Some smaller chargers, like 2 amps, have no fan. But that would take a long time.

For a very short visit, it might be possible to disable the fan and get 20 min of charge without frying the charger. Or not.

Some have been using sealed power supplies for bulk charging. See a thread in this section with LED power supply in the title. Perhaps you could use one of these more rugged, and silent power supplies for your opportunity charging. Then leave the fan cooled unit at home.

Dogman, how right you are, what is loud to one people is not even noticeable to another.

I like the idea of opportunity charging, especially with a 6amp charger, since just 1 hr of charging would replenish the battery plenty to continue or get home (should I be really far away).

IAN…

 

[dnmun]

i have one of the headway 48V3A chargers in the black plastic case and it makes almost no noise from the fan.

 

[imorton]

i have one of the headway 48V3A chargers in the black plastic case and it makes almost no noise from the fan.

Good to know, since I have had a few 24v & 48v SLA chargers and they were very quiet.

This is the 48v 6a charger I was contemplating from BMSbattery, and I hope it's quiet enough.

http://www.bmsbattery.com/alloy-she...po4li-ionlead-acid-battery-ebike-charger.html

I'm hoping that by putting the small 48v 9Ah Headway pack and the 6amp charger in a grocery bag, I could go into a restaurant, coffee shop, etc… and plug it into a wall outlet near my table and charge for an hour (should I need to) just like people do with laptops etc.… I find that there are not many "outdoor plugs" to use to recharge in my city

I guess there shouldn't be any problem with laying the headway pack in the bottom of the bag and putting the charger on top of the pack and charge away for an hour. I don't imagine there should be any issues with noise, heat, etc…?

 

[dnmun]

those alloy chargers are the noisy ones. that is an EMC charger and it does make more noise than the little plastic cased chargers.

 

[imorton]

those alloy chargers are the noisy ones. that is an EMC charger and it does make more noise than the little plastic cased chargers.

Hmmmm, more noise.. Ahhh well… I guess most 6amp chargers probably need a fan…

I guess by leaving the headway pack & the charger in the bag while I charge, hopefully it will cut down some of the noise not to disturb people.

Mind you, I was in McDonalds the other day and plenty of people are charging their laptops, cell phones etc… I did notice that there is plenty of plugs inside on most walls, and the noise level in there was fairly noisy to begin with

Hopefully I won't get "thrown out"…. hihihihihi

 

[imorton]

Has anyone had any problems while trying to charge their "portable battery packs" indoors… like in a restaurant, coffee shop, library, shopping center cafeteria area etc…?

What has been the other patrons reactions, since it could look like I am carrying a dangerous item in my bag.

Anyone had any incidents or comments?

IAN…

 

[Demosthenes]

I think the most nervous I've been about charging my battery in a public place was on a ferry, and I had no problems. My battery is a duct tape special too (no heat shrink, just duct tape) I think the biggest thing is don't leave it unattended, that is a baaaad idea. As long as you are right there to answer people questioning what it is, you'll be fine.

My 6A charger (http://www.batteryspace.com/smartcharger6afor518v14cellsli-ionbatterypack110vstandardfemaletamiyaplug.aspx) is quite noisy. I think it would probably still be heard in a McDonalds, this is by far the biggest obstacle to bringing it in places, I prefer to find outdoor plugs and just park the bike by them. (I was charging in a washroom at a provincial park once, the hand dryer was louder than the charger, but not by much, thing is bloody loud!)

 

[imorton]

Hmmmm, sounds I'll have to wait and receive that 6a charger to see how loud it is. I may end up only using indoors on those necessary recharges.

IAN…

 

[dogman dan]

It will be heard, but I doubt most people will give a damn. It's not an annoying noise, unless your fan has a bad bearing. It's just a whirring noise, not a scree scree scree, shrieking sound.

If it ever becomes a problem, which I doubt, there are 350w power supplies that are silent.

My personal experience is all charging at outdoor plugs.

 

[imorton]

It will be heard, but I doubt most people will give a damn. It's not an annoying noise, unless your fan has a bad bearing. It's just a whirring noise, not a scree scree scree, shrieking sound.

If it ever becomes a problem, which I doubt, there are 350w power supplies that are silent.

My personal experience is all charging at outdoor plugs.

Thanks for the tip about the 350w silent ones. Do you have a link for those by any chance?

IAN