bluovalguy
100 mW
- Joined
- Dec 8, 2013
- Messages
- 40
Hi folks, I'm new here. Just put together a light assist setup on a 700c hybrid bike with a Q100, 12a elifebike controller modified to 18a, and a Greenworks 40v 4ah g-max battery. I read/learned a lot on here before jumping in, lots of great info here!
I gambled on the g-max battery after reading the post below.
http://endless-sphere.com/forums/viewtopic.php?f=14&t=46110
EVEE was right, this battery is awesome. Here's the scoop after taking it apart. (tamper resistant torx bit required, then peel the labels, the bottom one will stretch/deform so don't do this if you want to keep it under warranty.)
-UR18650RX cells. From what little I can find, these are 22amp rated (11c), and Greenworks claims up to 2,000 cycles. (44a rating on the 4ah pack sounds about right given a single 2ah battery can power a mower that supposedly is nearly as powerful as a gas mower.)
-20 cells 10s2p (the 2ah battery is 10s1p, they must use the same bms as there is a box checked for either 2p or 1p)
-41.5v on the outside terminals at full charge.
-60 amp fuse on top of the bms.
-4ah pack weight 2.8 lbs. (my full bag weight with 2 batt's/charger/tools is right at 10lbs.)
*Edit* Link 1 shows a 10a(5C) discharge graph, about .3v drop. Link 2 is a PDF of some sort of presentation which is calling this a 20a cell and shows a 20a(10C) discharge graph (see page 21-22) with about .4v drop.
http://www.panasonic.com/industrial/includes/pdf/UR18650RX.pdf
http://media.nmm.de/54/sonnemann_panasonic_15.11.2012_15.00_26769354.pdf
I bought my first battery on amazon for $120 shipped, and charger for $30 shipped. After seeing what cells it had, I bought a complete mower on ebay that came with a 4ah battery and charger for $110 shipped. I think this was a return or display model because it looks brand new. Haven't tried mowing with it yet, but don't really care how it performs since this was a good deal for a spare battery/charger only.
So for the single battery installation, I took apart the charger and soldered wires to the back of the pins and use that in the bag as the battery holder. The + terminal isn't even used on the charger. I just leave it all in the bag to charge. Now that I have a spare battery, the second one fits in the bag and just takes a few seconds to swap out.
*Question- what effect would running these two in parallel have on battery life and range? Since I'm only operating at about 40% of the rated amps with 1, would running 2 provide much of a benefit? I don't want to just cram spade connectors into the battery terminals, seems like an accident waiting to happen. The second charger won't fit into the bag and I don't want to cannibalize that one just for the connector. Thoughts?
Thanks!
I gambled on the g-max battery after reading the post below.
http://endless-sphere.com/forums/viewtopic.php?f=14&t=46110
EVEE was right, this battery is awesome. Here's the scoop after taking it apart. (tamper resistant torx bit required, then peel the labels, the bottom one will stretch/deform so don't do this if you want to keep it under warranty.)
-UR18650RX cells. From what little I can find, these are 22amp rated (11c), and Greenworks claims up to 2,000 cycles. (44a rating on the 4ah pack sounds about right given a single 2ah battery can power a mower that supposedly is nearly as powerful as a gas mower.)
-20 cells 10s2p (the 2ah battery is 10s1p, they must use the same bms as there is a box checked for either 2p or 1p)
-41.5v on the outside terminals at full charge.
-60 amp fuse on top of the bms.
-4ah pack weight 2.8 lbs. (my full bag weight with 2 batt's/charger/tools is right at 10lbs.)
*Edit* Link 1 shows a 10a(5C) discharge graph, about .3v drop. Link 2 is a PDF of some sort of presentation which is calling this a 20a cell and shows a 20a(10C) discharge graph (see page 21-22) with about .4v drop.
http://www.panasonic.com/industrial/includes/pdf/UR18650RX.pdf
http://media.nmm.de/54/sonnemann_panasonic_15.11.2012_15.00_26769354.pdf
I bought my first battery on amazon for $120 shipped, and charger for $30 shipped. After seeing what cells it had, I bought a complete mower on ebay that came with a 4ah battery and charger for $110 shipped. I think this was a return or display model because it looks brand new. Haven't tried mowing with it yet, but don't really care how it performs since this was a good deal for a spare battery/charger only.
So for the single battery installation, I took apart the charger and soldered wires to the back of the pins and use that in the bag as the battery holder. The + terminal isn't even used on the charger. I just leave it all in the bag to charge. Now that I have a spare battery, the second one fits in the bag and just takes a few seconds to swap out.
*Question- what effect would running these two in parallel have on battery life and range? Since I'm only operating at about 40% of the rated amps with 1, would running 2 provide much of a benefit? I don't want to just cram spade connectors into the battery terminals, seems like an accident waiting to happen. The second charger won't fit into the bag and I don't want to cannibalize that one just for the connector. Thoughts?
Thanks!