Man_dizel said:Does graupner charger need external power to work? Or is it stand alone unit? I'm about to start my project and think that it's time to order the charger unit. What other chargers work for my planned 13s3p 26650 batteries?
ecross said:Man_dizel said:Does graupner charger need external power to work? Or is it stand alone unit? I'm about to start my project and think that it's time to order the charger unit. What other chargers work for my planned 13s3p 26650 batteries?
-thanks for your good question
-the graupner ultramat 18 is a stand alone charger with inside power supply, 120-230Vac input and 12V input![]()
-The AC input is about 90W and the add. 12Vdc input is about 300W
-the Graupner ultramat 18 is a 1 - 12pcs Lipo charger, for your 13S you can`t use this charger![]()
-please tell us your 26650 batteries source![]()
-for your 13S battery you need some other charger, but there are only a few on the RC market like:
-Thunder 1430
-Grauper Ultramat 45
-Robbe E-1
-Hyperion 1420i
-I have test the Graupner, Robbe and Hyperion, because we have here also a service for this charger.
-My recomment 14S charger is the Hyperion, because with +24Vdc about 550W charger power
-My recomment 12S charger is the Graupner Ultramat 18, because AC and Dc input, 300W DC-power, easy SW. good price/power
-Robbe E-1 about 315W
-Graupner Ultramat 45 about 250W
Man_dizel said:I want a charger that is plug and play and don't want to work with external power an stuff. That's why I asked about the charger issue.
madin88 said:Man_dizel said:I want a charger that is plug and play and don't want to work with external power an stuff. That's why I asked about the charger issue.
Are these LiIon or LiFe cells and what cut off voltage do they have?
Is the battery removeable or fix installed on the bike?
Another option would be to install a BMS on the bike and simple charge with a cheap "power supply unit". For your 500W bafang you don't need a expensive high power BMS.
This would be more plug and play if your battery is fix on the bike because you don't have to extra connect balancer wires.
Man_dizel said:The batteries is trustfire 26650 5000mah Li-ion batteries. Got 40 pieces from him. Will get it next month I hope. Cut off should be around 2.7v I think.
I was thinking of removable battery pack. Think that's best for my setup. Can someone recommend a good BMS for me then? Maybe that's the best way to go. So a simple charger will do it then?
madin88 said:Man_dizel said:The batteries is trustfire 26650 5000mah Li-ion batteries. Got 40 pieces from him. Will get it next month I hope. Cut off should be around 2.7v I think.
I was thinking of removable battery pack. Think that's best for my setup. Can someone recommend a good BMS for me then? Maybe that's the best way to go. So a simple charger will do it then?
I more mean charging cut off voltage. Are these trustfire LiFe (3,6V) or LiIon (4,1-4,2V)?
If you are going to remove your pack for charing, than a RC model charger is a good choice, but it can be very expensive if you want fast charging. For this you need a good charger AND a good power supply.
Just ordered hyperion 1420i from USA. $140 inclusive shipping. Now have to find 2 decent external power supply. Maybe some old computer power supply will work.Man_dizel said:madin88 said:Man_dizel said:The batteries is trustfire 26650 5000mah Li-ion batteries. Got 40 pieces from him. Will get it next month I hope. Cut off should be around 2.7v I think.
I was thinking of removable battery pack. Think that's best for my setup. Can someone recommend a good BMS for me then? Maybe that's the best way to go. So a simple charger will do it then?
I more mean charging cut off voltage. Are these trustfire LiFe (3,6V) or LiIon (4,1-4,2V)?
If you are going to remove your pack for charing, than a RC model charger is a good choice, but it can be very expensive if you want fast charging. For this you need a good charger AND a good power supply.
Its li-ion 4.1v
Fast charging is not an option that I want now. It's ok under night charging.
liveforphysics said:Soldering to the bottom of a can locally decomposes electrolyte in contact with it, even when cooling the cell.
No fuses or chaffing protection on balance taps.
Inadequate support for cells. Unfused discharge leads.
It also appears you are trusting the cell shrink wrapper alone with no additional chaffe protection to prevent can/can shorts from adjacent cell rows at other potentials.
May last OK in a stationary application, and I agree the battery should make a bike move, but I wouldn't trust that pack for anyone who takes offence to radom fires.
Just my $0.02
Man_dizel said:Just ordered hyperion 1420i from USA. $140 inclusive shipping. Now have to find 2 decent external power supply. Maybe some old computer power supply will work.
Thanks a lot. One single Hyperion should do the work for me I think. Does anyone know how long time it takes to charge 48v 15ah Li-ion batteries with one single Hyperion and one 12v power supply? And with 24v 400w?LSBW said:Man_dizel said:Just ordered hyperion 1420i from USA. $140 inclusive shipping. Now have to find 2 decent external power supply. Maybe some old computer power supply will work.
I'm using since March dual Hyperion 1420i for charging, with 8 IBM small factor desktop power supplies for two configs of 2S2P (24v, 20 Amp). Works pretty good.
You just need to connect in ATX connector green #16 pin to the ground, to turn PS ON, and grey #8 pin to +5 volt to indicate your PS is good to go.
cwah said:liveforphysics said:Soldering to the bottom of a can locally decomposes electrolyte in contact with it, even when cooling the cell.
No fuses or chaffing protection on balance taps.
Inadequate support for cells. Unfused discharge leads.
It also appears you are trusting the cell shrink wrapper alone with no additional chaffe protection to prevent can/can shorts from adjacent cell rows at other potentials.
May last OK in a stationary application, and I agree the battery should make a bike move, but I wouldn't trust that pack for anyone who takes offence to radom fires.
Just my $0.02
you mean soldering cell is inadequate and will damage them?
cwah said:makes sense!! I was wondering why they need so much glue between cells, but as you said, a short can happen because of chafe.
How can you prevent chafe on balance lead? and why do we need fuse on balance lead? I usually only have fuse on main leads
liveforphysics said:That tiny wire with high temp jacketing is fine.
To me, that pro pack seems like inadequate wire routing and protection for a pack that is used in a high vibration environment (bicycle), unless the wire jacketing is something pretty special, because there are plenty of spots it's going too flop around and chafe in there if shaken/bumped around adequately. Getting packs to survive a shaker table that simulates long periods of bumping down a road is not easy, and what chaffing can do would amaze you guys.
agniusm said:This why I think cell holders are very good for diy pack building. First they insulate cans negative edge by lifting it of yhe cell. Now you must spot weld the tabs. Second, it leaves some 2mm gap between the cells which could be used for balance wire routing and introduces some cooling. This is what I will be doing for my next battery along with thermal fuses.
t3sla said:agniusm said:This why I think cell holders are very good for diy pack building. First they insulate cans negative edge by lifting it of yhe cell. Now you must spot weld the tabs. Second, it leaves some 2mm gap between the cells which could be used for balance wire routing and introduces some cooling. This is what I will be doing for my next battery along with thermal fuses.
That not only enable greater airflow for cooling, they reduce vibration issues.
If you are going for a high discharge setup take note of the C rating VS Tempreture, sure you can push allot of the newer NMC tech but there is a decent heat trade-off and you have to consider the effects on the SEI layer when you cluster them with no venting under high load (Right?)
http://www.comsol.com/stories/kobelco_lithium_ion_batteries/full/
One factor to look out for is the quality of your welds, using a crummy ebay welder won't be adequate, I've seen tabs get hot with packs only pushing 500/800W, so a multi-kW setup is going to be exponentially taxing.
liveforphysics said:cwah said:liveforphysics said:Soldering to the bottom of a can locally decomposes electrolyte in contact with it, even when cooling the cell.
No fuses or chaffing protection on balance taps.
Inadequate support for cells. Unfused discharge leads.
It also appears you are trusting the cell shrink wrapper alone with no additional chaffe protection to prevent can/can shorts from adjacent cell rows at other potentials.
May last OK in a stationary application, and I agree the battery should make a bike move, but I wouldn't trust that pack for anyone who takes offence to radom fires.
Just my $0.02
you mean soldering cell is inadequate and will damage them?
It's not inadequate from an electrical connection stand point, it's just ensuring every cell with a soldered joint to them IS damaged internally. The solvents decompose and introduce gas at best when holding the case at >150C to get the solder to wet the can, so you know you've damaged them just building it.
You guys are aware that the can's are all the negative terminals right? And those in series are touching can's with other potentials and just relying on a very thing bit of shrink rubbing on shrink where the edges of cells contact each-other to prevent fire right? This is why even on the very shitty ebay 18650 packs they put hot-glue and a layer of fish paper or even card-stock paper or something between the rows of series groups.
Shrink does NOT chafe on shrink forever before it wears through, I can assure you of this. Likewise, unfused balance tap leads of that heavy gauge of wire cause some excitement.