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docnjoj
1 GW
Interesting! Competition at its finest!
otherDoc
otherDoc
K-ray
1 W
My limited experience with tenergy has shown cell capacities to be
somewhat exagerated. I'd be suprised if those truely are 14ah.
Maybe more like 10ah-12ah. By comparison, 16 lifebatts bought with
the group purchase @ $480, is about 13lbs. Granted a BMS is also required,
but I think a much wiser choice for a few more bucks. :wink:
Kevin
somewhat exagerated. I'd be suprised if those truely are 14ah.
Maybe more like 10ah-12ah. By comparison, 16 lifebatts bought with
the group purchase @ $480, is about 13lbs. Granted a BMS is also required,
but I think a much wiser choice for a few more bucks. :wink:
Kevin
docnjoj
1 GW
Agree!
otherDoc
otherDoc
nutsandvolts said:
What you have to compare are these critical specs shown for the LiFeBATT Cells here:
LiFeBATT 40138 Cells: 3.3V / 10 Ah
Maximum Discharge Current (continuous) 120A
Maximum Discharge Current (18s pulse) 140 A
Maximum Charge Current 30A
Cycle Life (minimum) 3,000 cycles, Capacity 7200 mAh
Compare the same Tenergy specs. to these to get a fair idea of how they truly rate.
Best,
Don Harmon
Ypedal
100 TW
Quote " Standard discharging rate: 14Amp ( Recommended and warranted) "
Would work on 20amp controllers, you would severely stressing them on a 40 amp controller.
You still have to assemble the pack, wire it up, add a thermistor, find a suitable charger ( all things not horribly hard to do.. but still requires more money .. and time )
Nimh get hot when charged, and hot when used, for longer life it's usually best to let them cool off between cycles. if this works with your schedule then it's o k.
Tenergy as a tendency to exagerate a bit at times. so rated capacity etc may not be exactly as advertised..
Since i've switched to lithium.. i just can't go back.. self discharge and the heat factor made them less attractive of the long run ( still better than SLA tho ! )
Would work on 20amp controllers, you would severely stressing them on a 40 amp controller.
You still have to assemble the pack, wire it up, add a thermistor, find a suitable charger ( all things not horribly hard to do.. but still requires more money .. and time )
Nimh get hot when charged, and hot when used, for longer life it's usually best to let them cool off between cycles. if this works with your schedule then it's o k.
Tenergy as a tendency to exagerate a bit at times. so rated capacity etc may not be exactly as advertised..
Since i've switched to lithium.. i just can't go back.. self discharge and the heat factor made them less attractive of the long run ( still better than SLA tho ! )
timbits
1 mW
almost 16 months ago I bought 20 of these 14AH cells from all-battery.com and constructed a 24 volt pack for my 360 watt cyclone motor. Peak amps I pulled from them never exceeded 34Amps, most of the use was in the 10-15 amp range. I was quite happy with them for the first 12 months or so ( i did use them quite regularly) then they started to not have the same capacity and my range dropped by about 1/3 over the next 3-4 months. Perhaps some of the cells are losing it or they need balancing? Could be a few cells that are weak. Haven' t had the time to really check into that. I now use Lifepo4 , and wouldn't go back to Nimh, but that is just my opinion.
Hi
They are supposed to be good cells though as NIMH go, i have been using a pack of NIMH for 2 x years on my bike pulling 37A max at 48V, whilst they sag a little under heavy load I could get 14AH from them when they were new, they can still put out the amps its just that they sag now under load.
NIMH is a mile better than SLA, their 2 years hard daily service is very good and they have been worth every penny, I am swapping them out for 2 x 37V 10AH lipo packs soon but will still use them in the BMX which only ever goes out on short runs to the shops and the pub :lol:
The Lifebatt deal is pretty hard to beat right now, if the group buy goes ahead and more folks test and report back about these cells I can only see more of them hitting the shores from the factory and in turn the price should drop and make them more affordable, this will of course force the price of NIMH to drop accordingly. One advantage of NIMH is you dont need a BMS this is a big plus however the specs of life batteries override this, however you can squeeze a little more out of them 14AH form an F cell from new is pretty hard to beat.
At 30 bucks a cell though Life batteries are going to be very hard to beat and they have a 14AH cell coming out as well.
Knoxie
They are supposed to be good cells though as NIMH go, i have been using a pack of NIMH for 2 x years on my bike pulling 37A max at 48V, whilst they sag a little under heavy load I could get 14AH from them when they were new, they can still put out the amps its just that they sag now under load.
NIMH is a mile better than SLA, their 2 years hard daily service is very good and they have been worth every penny, I am swapping them out for 2 x 37V 10AH lipo packs soon but will still use them in the BMX which only ever goes out on short runs to the shops and the pub :lol:
The Lifebatt deal is pretty hard to beat right now, if the group buy goes ahead and more folks test and report back about these cells I can only see more of them hitting the shores from the factory and in turn the price should drop and make them more affordable, this will of course force the price of NIMH to drop accordingly. One advantage of NIMH is you dont need a BMS this is a big plus however the specs of life batteries override this, however you can squeeze a little more out of them 14AH form an F cell from new is pretty hard to beat.
At 30 bucks a cell though Life batteries are going to be very hard to beat and they have a 14AH cell coming out as well.
Knoxie
needWheels
1 kW
- Joined
- May 27, 2008
- Messages
- 481
It's tenergy so only count on it being 10ah.
If I had that much to spend I'd definitely go LiFePo4.
A charger for that capacity NiMH would probably be at least $100, otherwise you'd be waiting 10+ hours for it to charge!
If I had that much to spend I'd definitely go LiFePo4.
A charger for that capacity NiMH would probably be at least $100, otherwise you'd be waiting 10+ hours for it to charge!
safe
1 GW
- Joined
- Dec 22, 2006
- Messages
- 5,681
The SubC's from Tenergy are rated at up to 10C. These large capacity cells from Tenergy are only rated at 1C. They cost about the same for the same capacity so you end up with 1/10 the true power this way.
...I looked at the idea, but chose the SubC's for this reason. The day they start to make large sized NiCads or NiMhs with high "C" rates like the SubC's is the day that LiFePO4 could have some competition. But for now if you want to go big cell you need to go LiFePO4.
