llile
1 kW
- Joined
- Dec 18, 2010
- Messages
- 457
I'm looking into a battery build, but here are some big picture conclusions.
I'm sort of racing a PING build against a LIPO build. As I already have some PINGs, that pack has the cost advantage, and I would expand the range by adding some PINGs. But I also might just start fresh for a new bike, with a battery matching the motor. The PIng is really a bit undersized to drive the motor I am considering.
This is a honkin battery, because it is powering a vehicle that should go pretty fast and pretty far. Right now I am estimating 50 WH/Mile and need a 50 mile range. More of a motorcycle than a bicycle. Call it a tiny car then. Range is about 20% higher than I actually expect to go, to treat batteries kindly in their old age. I'll get some tighter measurements of the WH/Mile, and I'd liek it to go down to a bout 30 WH/mile with a nice fairing, but here is the big picture stuff:
This would require 4 36V 15AH PINGs. Total cost, including chargers but not including a case, andersons, shipping, some wire and a few other accoutrements, for PINGs would be $2132US. Total weight 22.4 KG/49.28 LBS
Doing this with LIPO, using Turnigy 5000mAH 6S to make a 7P3S pack, and buying a charger and power supply, a bunch of anderson stuff, shipping, and methods' parallel expansion board LVC/HVC system, comes to $2052 minus a case. Total weight 16.7 KG/36.7 lbs We'll get into all those other details later of what charger and so forth.
Here is the rest of the big picture data:
[pre]Spec Ping Lipo
$/WH $0.99US/WH $0.88US per WH
Grams/WH 10.4 G/WH 7.1 G/WH
Total Weight 22.4KG/49.28 LBS 16.6KG/36.7 Lbs
Total WH 2160 WH 2331 WH
Range 43.2 Mi 46.62 mi
Total Cost minus case $2132US $2052US[/pre]
So, if all my head-scratching is correct, cost is about the same for both packs, LIPO carries a little more juice at a little less cost per watthour, PING is 34% more weight.
Note these figures neglected Depth of Discharge, and so are optimistic regarding range and $/WH among other things. Will be corrected in a later post -llile
Pings are simpler to connect and charge. Pings come with a charger and BMS, and one charger per pack plugs into one anderson per pack. Ping chargers are small, light and cheap, so I carry them with me in a padded case and grab opportunity charges on the road or the trail. And I have some already. Maybe they stay with the other bike?
Smaller lipos get more expensive if you use the same charger. Lipos are cheaper, and cheaper per WH! Who'd a thought it? Lipo has a bigger learning curve, will need a bunch of paralleling boards, plug/unplug a spaghetti of wires every time you charge, a more expensive charger and some more fire risk, risk being mitigated by using a really good quality charger and an automatic LVC/HVC circuit. (And maybe a concrete charging bay with a smoke alarm?)
Now, since I already have a couple of PINGs, they have the cost advantage if I want to expand my pack. However, the LIPO has 12 lbs weight advantage. Less than I expected. Bit of a size advantage too.
I am surprised that a PING battery is only half the wieght of a lead acid deep cycle ( I looked up the price and wieght of a sears diehard deep cycle just for fun). Pings really aren't that lightweight. Good ol' lead acid would be 21.7 gm/wh, so PING is half, LIPO is a third of lead acid weight. In the 80's we built an E-bike with two sears diehards strapped to the rear rack. What a dog!
Breakdown for all this is in next post.
I'm sort of racing a PING build against a LIPO build. As I already have some PINGs, that pack has the cost advantage, and I would expand the range by adding some PINGs. But I also might just start fresh for a new bike, with a battery matching the motor. The PIng is really a bit undersized to drive the motor I am considering.
This is a honkin battery, because it is powering a vehicle that should go pretty fast and pretty far. Right now I am estimating 50 WH/Mile and need a 50 mile range. More of a motorcycle than a bicycle. Call it a tiny car then. Range is about 20% higher than I actually expect to go, to treat batteries kindly in their old age. I'll get some tighter measurements of the WH/Mile, and I'd liek it to go down to a bout 30 WH/mile with a nice fairing, but here is the big picture stuff:
This would require 4 36V 15AH PINGs. Total cost, including chargers but not including a case, andersons, shipping, some wire and a few other accoutrements, for PINGs would be $2132US. Total weight 22.4 KG/49.28 LBS
Doing this with LIPO, using Turnigy 5000mAH 6S to make a 7P3S pack, and buying a charger and power supply, a bunch of anderson stuff, shipping, and methods' parallel expansion board LVC/HVC system, comes to $2052 minus a case. Total weight 16.7 KG/36.7 lbs We'll get into all those other details later of what charger and so forth.
Here is the rest of the big picture data:
[pre]Spec Ping Lipo
$/WH $0.99US/WH $0.88US per WH
Grams/WH 10.4 G/WH 7.1 G/WH
Total Weight 22.4KG/49.28 LBS 16.6KG/36.7 Lbs
Total WH 2160 WH 2331 WH
Range 43.2 Mi 46.62 mi
Total Cost minus case $2132US $2052US[/pre]
So, if all my head-scratching is correct, cost is about the same for both packs, LIPO carries a little more juice at a little less cost per watthour, PING is 34% more weight.
Note these figures neglected Depth of Discharge, and so are optimistic regarding range and $/WH among other things. Will be corrected in a later post -llile
Pings are simpler to connect and charge. Pings come with a charger and BMS, and one charger per pack plugs into one anderson per pack. Ping chargers are small, light and cheap, so I carry them with me in a padded case and grab opportunity charges on the road or the trail. And I have some already. Maybe they stay with the other bike?
Smaller lipos get more expensive if you use the same charger. Lipos are cheaper, and cheaper per WH! Who'd a thought it? Lipo has a bigger learning curve, will need a bunch of paralleling boards, plug/unplug a spaghetti of wires every time you charge, a more expensive charger and some more fire risk, risk being mitigated by using a really good quality charger and an automatic LVC/HVC circuit. (And maybe a concrete charging bay with a smoke alarm?)
Now, since I already have a couple of PINGs, they have the cost advantage if I want to expand my pack. However, the LIPO has 12 lbs weight advantage. Less than I expected. Bit of a size advantage too.
I am surprised that a PING battery is only half the wieght of a lead acid deep cycle ( I looked up the price and wieght of a sears diehard deep cycle just for fun). Pings really aren't that lightweight. Good ol' lead acid would be 21.7 gm/wh, so PING is half, LIPO is a third of lead acid weight. In the 80's we built an E-bike with two sears diehards strapped to the rear rack. What a dog!
Breakdown for all this is in next post.
