Finally ordered a DPV

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SLA and LiFe have comparable power, that is determined by the voltage. The LiPo packs have a higher voltage and less voltage drop so they do in fact have more "power" because the motor is revving a bit faster, but LiFe and SLA are running around the same voltages so there is no power gain, just burn time due to increased density.

For the UV18 you really only have the LiFe option from Rodney and that is an expensive battery pack due to the size. He is not making packs for the 26 and likely won't be. There are some guys that are, and if you hop over to the Cave Diving Forum there tends to be a bit more DPV discussion there
 
SLA and LiFe have comparable power, that is determined by the voltage.

True - but by that logic - ALL BATTERIES have comparable power. One would have to be HUGE compared to its counterpart to match the voltage.The difference is that Lipo and Life batteries can offer higher voltage than SLA in a smaller more compact footprint, therefore the battery itself can be the same size as a comparable SLA and offer more voltage.


Lipo has higher voltage, but not less voltage drop. That is linear between the two batteries. In fact, they are more similar then dissimilar. The big difference in the Viper is that the Life is 512 W and the Lipo is larger at 777.

Lithium IRON is slightly heavier than LIPO so to keep the battery at a similar physical size, the LIPO offer more watts.

Lithium Iron (life) is still a heck of a lot smaller thatn SLA for comparable output.

Thrust is the same, but run time is a lot longer on the larger LIPO. I went with lower price, longer cycle life vs the extra run time since I shouldnt need the run time (although....when Trace gets me into the caves I might.......)
 
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biggest difference is the lithiums are a 29V nominal battery, the SLA's are 24V, so the lithium turns the motor faster, more power, more speed. Voltage drop is under full load, and the LiPo's have a bit less voltage drop due to each cell being having larger capacity, which means top speed stays top speed. Power in what I was referencing was power felt by the diver by the motor, which is determined by voltage in, nothing else. Higher voltage=more power=more speed, SLA is 24v nominal, Lithium is 29V nominal so the motor turns faster which means the scooter goes faster and can pull harder, this is why the UV40 has faster top speed and more thrust than the UV18/26's

If you ask Rodney and any of the divers that have had these two in the water next to each other, the LiPo has a lot more oomph and is noticeably faster in the water than the LiFe, you made the right decision for your diving, but most of the cave divers buck up for the LiPo because the difference is really obvious. For ocean diving it doesn't make sense, but you don't see a lot of LiFe vipers in the wild in cave country.
 
biggest difference is the lithiums are a 29V nominal battery, the SLA's are 24V, so the lithium turns the motor faster, more power, more speed. Voltage drop is under full load, and the LiPo's have a bit less voltage drop due to each cell being having larger capacity, which means top speed stays top speed. Power in what I was referencing was power felt by the diver by the motor, which is determined by voltage in, nothing else. Higher voltage=more power=more speed, SLA is 24v nominal, Lithium is 29V nominal so the motor turns faster which means the scooter goes faster and can pull harder, this is why the UV40 has faster top speed and more thrust than the UV18/26's

If you ask Rodney and any of the divers that have had these two in the water next to each other, the LiPo has a lot more oomph and is noticeably faster in the water than the LiFe, you made the right decision for your diving, but most of the cave divers buck up for the LiPo because the difference is really obvious. For ocean diving it doesn't make sense, but you don't see a lot of LiFe vipers in the wild in cave country.


Right - but your comparing a SLA to Lipo on the UV series. Thrust on the Viper between a Life and Lipo is the same (55 lbs)? Thrust on the UV series goes from 45lbs to 55 lbs with a lipo upgrade.


So on a UV upgrade - the LIPO provides more thrust - but according to SS, on the viper series...the thrust is the same whether it is a life or a lipo. The only difference is the run time.


Right?


And I completely agree and understand why cave country would have more Lipo and less life. If/when caves are applicable - maybe Ill convert?

I almost did cave last week but then I had a work trip. At some point in the next year Im doing cave training, I just have to find the time. By the time Im ready for a scooter in a cave, maybe Ill need another one!
 
Right - but your comparing a SLA to Lipo on the UV series. Thrust on the Viper between a Life and Lipo is the same (55 lbs)?

I'll tell you now, a viper life and viper lipo have very different thrusts. I know what the specs say, but my crotch begged to differ. Many people I've spoken to on this topic had the same experience.

Uv <life <lipo <magnus
 
this thread actually prompted me to start a request for an updated Tahoe Benchmark to be completed because something is wrong with Rodney's numbers. The UV40 pulls harder than the UV18/26, it should, but the LiPo Viper pulls harder than the LiFe, and according to the last Tahoe, the Magnus pulled harder and was faster but the range numbers were all wonky. So either the LiFe isn't pulling as hard or as fast as Rodney claims, or something else is going on.

either way, as I branch into this shortly, it will be with a UV26 with a LiFe conversion inside of it, and due to the size it will have ranges far beyond any other scooter in the lineup, just won't be quite as fast
 

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