Tesla home battery pack and DPV battery pack Technology

[Dr. Lecter]

It's cool, Tobin--you keep right on building giant battery packs for inefficient scooters with shaft seals and no gas gauge. I'm sure nobody will mind a bit.

 

[cool_hardware52]

It's cool, Tobin--you keep right on building giant battery packs for inefficient scooters with shaft seals and no gas gauge. I'm sure nobody will mind a bit.

As fast as we can manage at the moment…..

one of the advantages of building after market goods for goods with a huge "installed base"



Tobin

 

[andrewy]

Tobin absolutely right. major cost is in 1. designing the pack and 2. supporting it. cells are cheap i can get 18650 panasonic cells for 2.20$ a cell, i had built 50ah batteries under $400 with proper bms and charger, however i would never sell one to general public As long as u have proper bms and common sense regular burn in check and whatsup meter, u dont need any real time charge monitors , although i would get one if it be cheap enough.

 

[eelnoraa]

I am no expert in Li batteries either but I believe cycles are not the only factor in lifespan. The batteries will suffer some losses based on time alone and if not exercised regularly that degradation will occur even quicker. None of the BMC's in current generation designs (that I'm aware of) allow any user interaction to set high and low voltages. So you can only guess at it with runtime and what your user provided/installed data logger tell you. Most packs don't even offer a simple capacity display so that you can easily stop charging at that 80-90% mark.

This is actually very easily done. You can tell the "fullness" of a LiOn cell by measure the voltage needed to charge the cell. My previous work tell me that a 18650 type of cell is at full charge depth at about 4.3V. All you need to do to prevent over charge (keep it from 100%) is to reduce the charging voltage, say to 4.1V. In practice, it is a little more complicated, but you really don't need a charging monitor to tell the status of the charge. For large pack, it is more complicated because cells are in series. So it is hard to tell how the voltage is disturbing amongst the cell from the charging voltage only.

 

[Akoni]

Ah, hardly.

I've designed and sold rechargeable battery powered devices for 30+ years. IMO "gas gauges" are a gimmick that almost no user needs. Far better to start with more than enough battery.

I understand that is your opinion but not everyone holds the same opinion. I also agree that is better to have more capacity and is why my scooters have more than ample capacity.

If battery capacity is "mission critical" who starts with less than a full charge? No one I dive with.

If battery capacity is "mission critical" who plans on using more than some fraction (1/2's 1/3's) of the known, proven capacity? No one I dive with.

If battery failure (exhaustion) is life threatening who doesn't include redundancy in their planning, i.e. spare scooter, back up light etc.? No one I dive with.

Determining useful range is of course necessary to plan, but that doesn't require real time display, it's easy to determine via data loggers or even returned capacity at time of charge.

Can detail for me exactly how real time data will change your dive planning in ways that a data logger cannot? What I said is that while I don't expect Li scooter batteries to come down in price, I would expect that as cell prices drop manufacturers will improve their designs to include simple, UNIVERSALLY agreed upon features such as data loggers. Eventually, the next extension to built-in data logging is more convenient display of that data. The only way this is different from what you're saying is that you believe the user should either not care for additional features or should add it themselves but you're not going to add it to your product. Aces! Good on you. You build a good product as evidenced by all the kool-aid drinkers rising up to defend your product and their equipment choices. I have no issues with what people buy or with what you sell. Actually, I didn't know that DSS chargers had some in-built information display beyond a charging/done charging LED. I applaud that. Real time or convenient data display only make it easier to to continue to execute best DPV practices. This is why real time displays are present in other means of conveyance such planes, trains and automobile....and space shuttles, and manned rockets...basically any means of conveyance more complicated than a skateboard. You don't want to incur the expense of adding that functionality to your designs...rock on. Again, I wasn't addressing Dive Xtra or DSS products directly. At times, I have spent my hard earned money, that I really didn't 'need' to spend, upgrading to some DSS products because I thought they were better. While I'm set for scooters for quite some time with my currents rides, I expect that scooters will continue to evolve even if you don't think they should.


Tobin

Some thoughts in blue above...

 

[cool_hardware52]

What I said is that while I don't expect Li scooter batteries to come down in price, I would expect that as cell prices drop manufacturers will improve their designs to include simple, UNIVERSALLY agreed upon features such as data loggers. Eventually, the next extension to built-in data logging is more convenient display of that data. The only way this is different from what you're saying is that you believe the user should either not care for additional features or should add it themselves but you're not going to add it to your product. Aces! Good on you. You build a good product as evidenced by all the kool-aid drinkers rising up to defend your product and their equipment choices. I have no issues with what people buy or with what you sell. Actually, I didn't know that DSS chargers had some in-built information display beyond a charging/done charging LED. I applaud that. Real time or convenient data display only make it easier to to continue to execute best DPV practices. This is why real time displays are present in other means of conveyance such planes, trains and automobile....and space shuttles, and manned rockets...basically any means of conveyance more complicated than a skateboard. You don't want to incur the expense of adding that functionality to your designs...rock on. Again, I wasn't addressing Dive Xtra or DSS products directly. At times, I have spent my hard earned money, that I really didn't 'need' to spend, upgrading to some DSS products because I thought they were better. While I'm set for scooters for quite some time with my currents rides, I expect that scooters will continue to evolve even if you don't think they should.

So I take it your actual answer to my question is real time data display will do nothing to change your dive plannning......


Got it.

Tobin

 

[Akoni]

So I take it your actual answer to my question is real time data display will do nothing to change your dive plannning......


Got it.

Tobin

My actual answer to your question appears to make not one bit of difference as you just interpret it to service your 'truth'. This is like a bad GI3 impersonation.

Maybe you lack sufficient experience in hard overhead environments to where it limits the scope of your 'reality'?

Please send me all your unused SPG's as I'm sure you find those are not really needed either.

 

[Pullmyfinger]

It's cool, Tobin--you keep right on building giant battery packs for inefficient scooters with shaft seals and no gas gauge. I'm sure nobody will mind a bit.

I'm happy that he is making them.
Buying a battery from Tobin is on my list of "needs" in the near future.

I just have to decide which of my inefficient scooters I want to put it in.

I do see the advantages of the magnetic prop on the Genesis, however I am comfortable with the shaft seals on the Cudas.

That design has been in use since long before I became a diver; I'm ok with it.

I am not a designer, or an expert.....only the end user of a product.
But I do subscribe to the view that using a bigger battery is a good way to go.

I'm sure Genesis owners are realizing the same benefits in having a lot of battery capacity.

For me, I'll take a Fury battery.
I can tolerate the risk of unlikely shaft seal failure.

No doubt, I would be crying if a deal failed......but I will risk it.

The gauge is pretty "cool", but it wouldn't change how I approached planning a dive.

@Tobin: will your battery work with a Cuda650? Or only for the Cuda400?

 

[cool_hardware52]

@Tobin: will your battery work with a Cuda650? Or only for the Cuda400?

Any Cuda.

Tobin

 

[Dr. Lecter]

But I do subscribe to the view that using a bigger battery is a good way to go.

I'm sure Genesis owners are realizing the same benefits in having a lot of battery capacity.

I doubt we'd be very happy getting the same benefits: try comparing efficiency between the Cuda Fury and the Genesis scooters back from the last TBM tests. Bigger batteries are great. Needing a bigger battery to deliver the same performance because you're getting the DPV equivalent of terrible gas mileage? Not great.