Is lithium really safe ?

[KTP]

Originally Posted by CatNewBee

no, the second 100Ah are not fully usable, the voltage drop is massive beyond 40% SOC. In contrast, LFP deliver almost full usable capacity at constant voltage. Ways better!

According to the load voltage curve from Lifeline, their AGM batteries have the following voltage drop at the 8hr rate (45 amp draw on 375AH battery bank) assuming you have four batteries in series for a 48V system:

90% 12.6V * 45A = 567W * 4 batteries in series = 2268W to motor
80% 12.51V = 2252W to motor
70% 12.39V = 2230W to motor
60% 12.25V = 2205W to motor
50% 12.11V = 2179W to motor <--LiFePO4 187.5AH bank is dead here
40% 11.98V = 2156W to motor
30% 11.79V = 2122W to motor
20% 11.32V = 2037W to motor
10% 11.15V = 2007W to motor
0% 10.50V = 1890W to motor

So you maintain over 2kW to the motor all the way down to 10% remaining on the Lifeline AGM. Hardly what I would call "massive" drop. But this is only facts and stuff...don't let it deter the thread

[bouncycastle]

Originally Posted by KTP

According to the load voltage curve from Lifeline, their AGM batteries have the following voltage drop at the 8hr rate (45 amp draw on 375AH battery bank) assuming you have four batteries in series for a 48V system:

90% 12.6V * 45A = 567W * 4 batteries in series = 2268W to motor
80% 12.51V = 2252W to motor
70% 12.39V = 2230W to motor
60% 12.25V = 2205W to motor
50% 12.11V = 2179W to motor <--LiFePO4 187.5AH bank is dead here
40% 11.98V = 2156W to motor
30% 11.79V = 2122W to motor
20% 11.32V = 2037W to motor
10% 11.15V = 2007W to motor
0% 10.50V = 1890W to motor

So you maintain over 2kW to the motor all the way down to 10% remaining on the Lifeline AGM. Hardly what I would call "massive" drop. But this is only facts and stuff...don't let it deter the thread

Unfortunately for us mere mortals we need to try to and figure out what this table means to us so I will try to have stab at it using a typical deep keel 24 foot cruiser boat as a example steaming in calm waters

I shall assume the craft does 3.5 knots at 2268W
rpm of prop unknown size and type of prop unknown

~45 amp draw on ~375AH makes ~8 = 0.125C or just over 10% of the battery capacity

The importance of this is if you ask ~50% capacity from the battery such as ~50 amp on ~100 AH battery you will be lucky to get ~50% the energy the battery has
Also it would be hard get a more than ~1 hour of the battery running with a AGM battery and many FLA type batteries wont even go there

Extreme C rates waste most the power in heat losses due to IR^2 making heat loses increase exponentially

So low C rates between ~8 % to ~12% as tops with ~20 % in extreme requirements in emergency use for AGM and FLA battery types to get battery to return the most useful power ratio over time .

Needless to say drawing the power from AGM and FLA battery over ~20 hours or ~0.05C will return the best power efficiency ratio over time but not much useful power for motors

So 24 foot boat doing 3.5 knots using 2268W over 8 hours might look more like this

1 hour ~2250W = 3.5 knots
2 hour ~2200W = 3.2 knots
3 hour ~2150W = 3.1 knots
4 hour ~2100W = 3.0 knots
5 hour ~2090W = 2.9 knots
6 hour ~2050W = 2.8 knots
7 hour ~2030W = 2.7 knots
8 hour ~2010W = 2.6 knots

23.8 miles completed


If the choice was to go at 4.5 knots the amp draws might be 100 amps range will drop probably look like ~11 miles range over ~ 3hours and 0.4C on 375AH

If the choice was to go flat out 5.5 Knots amp draws of ~200 amps range could drop to ~5 nautical miles over ~1 hour

The best energy ideal for many deep keel boats willl tend to be at ~60% of the ultimate waterline speeds
As we progress towards the max waterline speeds the power demands go up exponentially

The life span of FLA and AGM will benifit from not exceeding draw rates that will flatten the battery before ~8 hours
However that increases cost a lot
Many electric boat projects will opt to use rates in excess of this ideal such as ~20% draw down on the battery AH per hour but only for short duration and low ranges such as one mile range to exit the harbor

FLA and AGM can return OK life spans from ~20% demands abuse use for short duration of the battery if full and power is restored to battery shortly after the abuse such as battery recharged after ~4 hour sailing session

There might exist electric calculators that can inform the users of what to expect from any sets of battery used on various crafts so as to reduce risks of choosing the wrong sets of equipment for the boats

The problem with many of the Lithuim cells ls the cycle life divided into cost by power ratios often make them cost more than lead solutions

Li-ion 18650 type of cells have the highest power density ratio and can if sourced correctly and built by amateurs return benefits that exceed Lead Battery solutions but the cost risk ratio are high in this time .

If we used FLA battery golf car types at ~$100 X 8 = ~$800 for a 6V battery of 220 AH on a 20 foot sail boat
drawing ~30 amps for ~7 hours about ~1500W to motor
going at ~2,5 knots or range of ~15 Nautical miles
with a 550 cycle life
= about ~8200miles or about ~0.42cents a mile or $6.30 for each ~15 Nautical mile trip

(in realty closer to ~$8 a trip in terms of battery cost ife ratio with head winds and current and other factors added in ) .

NB the last ~100 cycles might drop from ~15 Nautical miles to ~10 Nautical Miles range with incremental drops in range with each cycle as batteries sulfate .

With AGM often costing double the price often you can nearly double those cost per nautical mile numbers so many AGM solutions for this type of boat will tend to be ~100 to ~150 AH to reduce costs but with reduced ranges .
They will often be the types that use ~2 miles ranges to enter and return to harbors where 220 amps weight and costs cannot be justified .

With most of the Lithuim families costs and power density in this time its easy to double or quadruple the costs again per mile over the AGM battery solutions in this time

With Lithuim ions 18650 cells using methods like sourcing batteries bulk cheaper and even buying slightly used types and building the packs as amateurs sometimes cost per Nautical have been able to match AGM costs .

Some might say well good old diesel works best is cheaper .

However when all costs are factored into most Diesel solutions they often come out even on 20 BHP inboards well north of ~$1 dollar a nautical mile

Many boats rarely used with winter summer maintenance costs can exceed easy ~$5 a mile

Much Bigger Diesel engines can pluck a number from the ether and then double it for luck and still be very wrong .

The marine environment is very harsh on diesel engines compared to land based diesel engine solutions



Back to safety electric solutions done right rarely have engine failures especaily at critical points like exiting a harbor .

Diesel engines can let you down at critical points when you need them most anything from water in the fuel to plant growth in the fuel tanks or pipe works and other mishaps

Electric battery fire hazards are low but if ignited tend to be tricky to stop fires without forward planning and suitble fire stoping solutions and training
the Lithium ion family of the LiPo type being the riskiest for fire and exlosions and LIFE types being the lest risky with 18650 type nearly as low risk as the LIFE types .

The FLA types have Hydrogen gas risks but has proved itself to be a rare event fire explosion risk if done correctly .
AGM battery types are probably the least risky for fires of the lead acid battery family

Diesel engines are also a risk for fires and depending the amounts of uel the risks increase .Cruising boats can and do often carry extra fuel on the decks in jerry cans which might risk to ignite from other fire sources .Diesel fuel fires are very difficult to stop once they start .

One 65 foot boat crossing the Atlantic engine room fire required three fire extinguishers to stop the fire and it was a local fire around the engine not so big but fuel lines were feeding the fire .

The least fore risk is to have no power source other than the sails not even solar cells or domestic battery or cooking solutions like gas or any electric power for domestic solutions .
Not too many sailing dingy s ever catch fire

Hopefully next year I will install a golf cart battery solution to a ~21 foot boat that i intend to buy if things work out but i probably opt for ~24 volt solutions . I would also if possible try to add a suitable 2kw gasoline (petrol Benzine ) generator to the mix to increase the range somewhat .

The prime reason is the 4 battery 24 volt combo of 220Ah will return a lot of good use for domestic battery demands with short engine runs to enter and leave harbors .

Boats above ~22 feet to about ~35 feet have to do the 8 battery 48 V solutions. Above that size starts to become mega serous costs


In few years time the costs of Lithium ion 18650 cells might drop enough to kill of lead acid but the jury is still out on that .

Realistically I cant see any type NiCads Or NiMh being useful for boats use,
NiMh types if they catch fire are nearly impossible to put the fires out as the Battery is filled with oxide materials that love to burn with great heat something like LiPo does. Also their power density is low with their 1.2volt per cell .

However the Li Ion 18650 cells makes great projects to replace the 12 lead acid solution for the tender dingy or 24/36 volt batteries for the electric bikes that device the boats .The learning curve from those projects can teach the solution for the future Li ion projects

Hope that helps the boating community

[john61ct]

Threads drift so much they get lost at sea

[boatpoker]

Originally Posted by bouncycastle

Unfortunately for us mere mortals we need to try to and figure out what this table means to us so I will try to have stab at it using a typical deep keel 24 foot cruiser boat as a example steaming in calm waters

I shall assume the craft does 3.5 knots at 2268W
rpm of prop unknown size and type of prop unknown

~45 amp draw on ~375AH makes ~8 = 0.125C or just over 10% of the battery capacity

The importance of this is if you ask ~50% capacity from the battery such as ~50 amp on ~100 AH battery you will be lucky to get ~50% the energy the battery has
Also it would be hard get a more than ~1 hour of the battery running with a AGM battery and many FLA type batteries wont even go there

Extreme C rates waste most the power in heat losses due to IR^2 making heat loses increase exponentially

So low C rates between ~8 % to ~12% as tops with ~20 % in extreme requirements in emergency use for AGM and FLA battery types to get battery to return the most useful power ratio over time .

Needless to say drawing the power from AGM and FLA battery over ~20 hours or ~0.05C will return the best power efficiency ratio over time but not much useful power for motors

So 24 foot boat doing 3.5 knots using 2268W over 8 hours might look more like this

1 hour ~2250W = 3.5 knots
2 hour ~2200W = 3.2 knots
3 hour ~2150W = 3.1 knots
4 hour ~2100W = 3.0 knots
5 hour ~2090W = 2.9 knots
6 hour ~2050W = 2.8 knots
7 hour ~2030W = 2.7 knots
8 hour ~2010W = 2.6 knots

23.8 miles completed


If the choice was to go at 4.5 knots the amp draws might be 100 amps range will drop probably look like ~11 miles range over ~ 3hours and 0.4C on 375AH

If the choice was to go flat out 5.5 Knots amp draws of ~200 amps range could drop to ~5 nautical miles over ~1 hour

The best energy ideal for many deep keel boats willl tend to be at ~60% of the ultimate waterline speeds
As we progress towards the max waterline speeds the power demands go up exponentially

The life span of FLA and AGM will benifit from not exceeding draw rates that will flatten the battery before ~8 hours
However that increases cost a lot
Many electric boat projects will opt to use rates in excess of this ideal such as ~20% draw down on the battery AH per hour but only for short duration and low ranges such as one mile range to exit the harbor

FLA and AGM can return OK life spans from ~20% demands abuse use for short duration of the battery if full and power is restored to battery shortly after the abuse such as battery recharged after ~4 hour sailing session

There might exist electric calculators that can inform the users of what to expect from any sets of battery used on various crafts so as to reduce risks of choosing the wrong sets of equipment for the boats

The problem with many of the Lithuim cells ls the cycle life divided into cost by power ratios often make them cost more than lead solutions

Li-ion 18650 type of cells have the highest power density ratio and can if sourced correctly and built by amateurs return benefits that exceed Lead Battery solutions but the cost risk ratio are high in this time .

If we used FLA battery golf car types at ~$100 X 8 = ~$800 for a 6V battery of 220 AH on a 20 foot sail boat
drawing ~30 amps for ~7 hours about ~1500W to motor
going at ~2,5 knots or range of ~15 Nautical miles
with a 550 cycle life
= about ~8200miles or about ~0.42cents a mile or $6.30 for each ~15 Nautical mile trip

(in realty closer to ~$8 a trip in terms of battery cost ife ratio with head winds and current and other factors added in ) .

NB the last ~100 cycles might drop from ~15 Nautical miles to ~10 Nautical Miles range with incremental drops in range with each cycle as batteries sulfate .

With AGM often costing double the price often you can nearly double those cost per nautical mile numbers so many AGM solutions for this type of boat will tend to be ~100 to ~150 AH to reduce costs but with reduced ranges .
They will often be the types that use ~2 miles ranges to enter and return to harbors where 220 amps weight and costs cannot be justified .

With most of the Lithuim families costs and power density in this time its easy to double or quadruple the costs again per mile over the AGM battery solutions in this time

With Lithuim ions 18650 cells using methods like sourcing batteries bulk cheaper and even buying slightly used types and building the packs as amateurs sometimes cost per Nautical have been able to match AGM costs .

Some might say well good old diesel works best is cheaper .

However when all costs are factored into most Diesel solutions they often come out even on 20 BHP inboards well north of ~$1 dollar a nautical mile

Many boats rarely used with winter summer maintenance costs can exceed easy ~$5 a mile

Much Bigger Diesel engines can pluck a number from the ether and then double it for luck and still be very wrong .

The marine environment is very harsh on diesel engines compared to land based diesel engine solutions



Back to safety electric solutions done right rarely have engine failures especaily at critical points like exiting a harbor .

Diesel engines can let you down at critical points when you need them most anything from water in the fuel to plant growth in the fuel tanks or pipe works and other mishaps

Electric battery fire hazards are low but if ignited tend to be tricky to stop fires without forward planning and suitble fire stoping solutions and training
the Lithium ion family of the LiPo type being the riskiest for fire and exlosions and LIFE types being the lest risky with 18650 type nearly as low risk as the LIFE types .

The FLA types have Hydrogen gas risks but has proved itself to be a rare event fire explosion risk if done correctly .
AGM battery types are probably the least risky for fires of the lead acid battery family

Diesel engines are also a risk for fires and depending the amounts of uel the risks increase .Cruising boats can and do often carry extra fuel on the decks in jerry cans which might risk to ignite from other fire sources .Diesel fuel fires are very difficult to stop once they start .

One 65 foot boat crossing the Atlantic engine room fire required three fire extinguishers to stop the fire and it was a local fire around the engine not so big but fuel lines were feeding the fire .

The least fore risk is to have no power source other than the sails not even solar cells or domestic battery or cooking solutions like gas or any electric power for domestic solutions .
Not too many sailing dingy s ever catch fire

Hopefully next year I will install a golf cart battery solution to a ~21 foot boat that i intend to buy if things work out but i probably opt for ~24 volt solutions . I would also if possible try to add a suitable 2kw gasoline (petrol Benzine ) generator to the mix to increase the range somewhat .

The prime reason is the 4 battery 24 volt combo of 220Ah will return a lot of good use for domestic battery demands with short engine runs to enter and leave harbors .

Boats above ~22 feet to about ~35 feet have to do the 8 battery 48 V solutions. Above that size starts to become mega serous costs


In few years time the costs of Lithium ion 18650 cells might drop enough to kill of lead acid but the jury is still out on that .

Realistically I cant see any type NiCads Or NiMh being useful for boats use,
NiMh types if they catch fire are nearly impossible to put the fires out as the Battery is filled with oxide materials that love to burn with great heat something like LiPo does. Also their power density is low with their 1.2volt per cell .

However the Li Ion 18650 cells makes great projects to replace the 12 lead acid solution for the tender dingy or 24/36 volt batteries for the electric bikes that device the boats .The learning curve from those projects can teach the solution for the future Li ion projects

Hope that helps the boating community

Way too much time in the bouncy castle

[bouncycastle]

THis link to Youtube is from a USA source Californian Guy who probably is the one the top Lithium Ion Guru,s of the planet

jehugarcia

https://www.youtube.com/channel/UCcMfCkN1juSa49DJFYltOTw



His projects include building a car that had range of 1000 miles using 18650 cells , building a VW combi van with LiFePO4 cells and power walls and many other projects including inverter testing and best Battery management and numerous other stuff

Whats interesting for boaters is he often is testing longevity of various cells and verifying if dealers are selling the real stuff or fake stuff .

What is interesting is he measures the value of the cells in terms of cost per AH so he will say the cells cost ~$2 per amp hour as a example

He also has done destruction to fire or explode of various cells which can help for safety issues

The next video listed below is interesting sales video which cover safety pushing the merits of the LiFePO4 type battery .

points of interest
The smaller battery is the more interesting as it doesn't require HAZMAT expensive shipping costs which can increase shipping costs anywhere from ~20% to 300% to the cost of shipping depending on if its local shipping or outside of the USA shipping
Also then don't forget import tax and VAT can be added to that outside the USA and some companies even add on packaging and handling costs for heavy outsize objects

The small 12volt 150AH LiFePO4 battery in the video costs were ~$1300 in the USA could exceed $2600 shipped to other parts of the world
The battery has 5000 cycle life to ~80% DOD or 2000 cycle Life of 100% DOD
Based on lowest figures $1300 that makes 1300/150= ~$8.70 per AH

The video compares this to ~200 amp hour AGM 12volt 220 battery with 50% DOD of 500 cycles or 25% DOD of 1200 cycle costing ~$560

Based on that figure $560 that makes 560/200= ~$8.70 a AH = $2.8 per AH
However that does not take into account the most lilky 5000 cycle life of the lithuim battery versus the most likly use ~500 cycle of the AGM which alters the figure again to look more like like this life cost ratio per amp below

LIFEPO4 ~5000 cycles of 80% of 150= 120 AH x5000= 600,000 AH life make it ~500.000 AH real world with losses means $1300/500,000 =$0.0026 cents per AH
for that LIFEPO4 Battery over probably ~13 .5 years one cycle per day or suggests $1300/13.5 years = ~$96 a year ( real world probably ~$100 a year )

The AGM with 500 cycle of 50% of 200AH = 100AH x 500 = 50,000 AH life means 560/50,000=$0.011 cent per AH
for that AGM Battery over probably ~1.36 years one cycle per day or suggests $560/1.36 years = ~$415 a year real world

You can use two AGM and do 25% DOD and reduce battary costs to ~200 a year but AGM figures suggest it will cost double the cost of the similar type LiFePO4

In real terms however the Golf cart 6volt battery with est ~750 cycle life at ~50% DOD often costing $100 each in the USA could nearly match the annual cost of the LIFePO4 if used daily one cycle regimes .
The video wont show this they compare LIFePO4 against the weaker solution the AGM
( again extra bias against AGM in video which are often cheaper than the video shows and can have interesting cycle lifes at ~50% DOD )

The T105 with 750 cycle of 50% of 220AH = 110AH x 750 = 82,500 AH life (2 battery) means $200/82,500=$0.0024 cent per AH
for that T105 Battery over probably ~2.05 years one cycle per day or suggests $200/2.05 years = ~$100 a year real world

What the video shows is if your doing a daily cycle such as domestic battery in live aboard boat with 80% DOD the costs and toughness of the battery even if it only returned 4000 cucle life would be hard to beat

What the video doesnt show is the T105 cna nearly match the LIFePO4 and you fork out the cost every 2 years in smaller amounts like 200 versu 1300
In Europe the T105 cost are closer to double the USA so about $200 per T105 so expect the LIFePO4 to be closer to $2600.
Not too many people will fork out for a LIFePO4 at those costs as many people will not keep the boat 13 years so would prefer to fork out $400 for the two T105

Factor in the average one time week user of boat unless they want the best bullet proof very safest most fire resistant battery and they are richer folk with the cash then a LIFePO4 battery isnt gonna happen in this time at those $1300 cost for most folk

The argument to use 4 of the LIFePO4 at $1300 a pop or $5,200 to electric drive say a ~24 to ~30 foot boat is probably not gonna happen often in this time when it compared to a diesel engine

There is lot of life yet to be had in the T105 until Lithium solutions drop a whole lot in costs in AH and per cycle AH

Enjoy the Youtube

[bouncycastle]

Sorry forgot the video link

KiloVault Solar Lithium Batteries

https://www.youtube.com/watch?v=qmL0pgPdzPE

[bouncycastle]

Originally Posted by boatpoker

Way too much time in the bouncy castle

If you had been stuck in some part of the planet with crippled boats from bad electric solutions you learn the time spent ashore figuring things out to work best can return the safe stress free cruising later on

I have seen a ~2 million dollar 65 foot top range sail boat crippled when it all went pear shaped
The boat left Portugal to sail to the Canary Islands. However it 8kW generator could not keep up with the daily demands of the ~7KW aircon the ~1 KW washing machine ,The ~1KW navigation self steering and host of other kilowatt demands like water maker.
To cover this energy gap the inverter using the banks of Batteries and the engines generator helped out. After a few days the Batteries melted down the engine generator burnt up and the 8Kw generator burnt up. The crippled boat with light 3 crew and manual winching and sailing equipment drifted for many days in light airs to get to get to the destination the Canary Island with bad food as no refrigerator to keep food fresh and worse no cold beers .
The solution when everything was fixed was to increase the generator size to 16KW and verify frequently the electric demands by training in the captain and crew on electric power demands .
The real issue was the boat was configured correctly for the charter work in the carrbeen islands and Mediterranean with daily sailing .
Every night the boat would dock at a marina and get power from there.The 8KW generator was able to keep up with demands with the buffer of the battery banks and invertors and engine generator .
However put the boat on long haul with the untrained crew on electric demands and they melted everything the boat spent over $50,000 fixxing the mess and had to wait for weeks in port for the spare parts .

When your on the sea with no radio and crippled or stuck in harbours waiting for parts you wish you had spent some time looking the story of electric power demands and battery failures are the stardust of destruction many a boats cruising plans and worse the end of the boat existence .

Even some daily sailors who never intended to travel far for whatever reason when driven offshore have suffered from not knowing the story of electric demands
This included in the past myself assuming spec sheets on battery power were correct to the AH .
Boy does that come to bite you in the rear end

Nowadays I invest in back up solutions like paraffin lights whatever just incase the best laid plans of mice and men are taken out when the boat fills with sea water and kills all the electrics

Drifting at sea inside liferafts because the electrics let me down isnt my cup of tea so prefer to plan ahead best as possible .

Some cruising boats will want to know should they invest in $1000 plus Lithium solutions versus ~$100 T105 or ~$300 AGM
Maybe I can help them know the swings and roundabouts of this choice which might keep their boats afloat when the dung hits the prop
I know numbers about batteries is like watching paint dry but trying to figure real numbers versus marina shop sales blurb can mean keeping the boat afloat when it goes pear shaped

[boatpoker]

Originally Posted by bouncycastle

I have seen a ~2 million dollar 65 foot top range sail boat crippled when it all went pear shaped leaving

Guess it wasn't as "top range" as you thought

[john61ct]

The ideal posts are short and on-topic.

[bouncycastle]

Originally Posted by boatpoker

Guess it wasn't as "top range" as you thought

Wasnt my boat they bend them i fix them nd I have made small fortune in the recycling centers from yuaghts and RV who have throw away the batteries they cooked .
One large boat I sorted cooked ~1 ton of lead acid batteries which made me enough cash in scrap metal to buy a inboard for the 30 foot bat i salvaged from the marina bone yard .
I also got my commission from the local marina for buying replacement batteries and installing them .
I will probaly stay in the bottom feeder section of cruising boats as I do my travels often on older smaller ~25 foot boats that if i need to exit stage left in a hurry i can sell up quickly and easily and grab a plane ticket out of there.
But keep those big boats wrecking their batteries whatever it keeps us marina rats alive with the crumbs from the tales when they wreck stuff .

Its the hapless run of the mill cruiser many with familys and often on tight budgets that can risk to be cuaght out with wrong data for batteries.
Worse sometimes this got them in a bad pickle.
There i try to pass on the information so as to help them not wreck their gear .

The best I can say on batteries are they are bad voodoo can never be trusted and if sea water comes in the boat will often wreck them just when you need them to pump out the water and often cost a mega fortune to replace outside of the USA

[CatNewBee]

What a long rant - and not slightly related to the thred.

Its about Lithium batteries and safety. No lead acid, no gennys...

[bouncycastle]

small ERROR in post 95 reference using two AGM annual costs
If you reduce the load to 25% DOD you more than double the cycle life from 500 cycles to 1200 cycles
That in effect reduces the costs from the figure used $200 ayear based on 500 cycles to more like $100 a year

Therefore we can say everything indicates mathematically AGM if you happy to live with extra weight of 400 amp versus 220 amps of the T105 or lighter LiFePO4 is about the same annual cost per year $100

Cost for LiFePO4 = ~$100 per year & safe fire type AGM would be marginally safer
cost for T105 = ~$100 per year Fire safe but mix with salt water = toxic gas
cost for AGM =~ $100 per year fire safest type valve sealed from atmosphere

Which all doesnt suprise me as the cost of everything in life is based on what the market will pay for the stuff
Cost rarely are based on logic so the battery sales guys try to even out the costs across all types of batteries or they might get stuck with old redundant battery stocks

[bouncycastle]

Originally Posted by CatNewBee

What a long rant - and not slightly related to the thred.

Its about Lithium batteries and safety. No lead acid, no gennys...

Thats like saying how safe is gun with no bulllets or human targets in the story .
Batteries are rarely stored as blocks of metal just in case they are needed and then hooked into a electrical network .

Batteries are all part of larger equation weight safety cost capital outlay return on investment size and type of boat and the type of generators or solar or wind or hydro power will all impact the system and then throw in is for domestic power needs or eletric power or hybrid needs .

Some Lithuims make a explosive mix or serious fire risk if charged the wrong way and some types of lithuims are able to take serous abuse even more than some AGM or T105

Those who find good solutions have often done serous research into the subject

Lithuims safety is all part of this scomplex story it nots a 41 cheese burger in fast take away

If itried to say x this y that in 5 sentences the battery nazi would jump all over me and show all sorts of examples where that doesn't apply

What I can tell you marina battery sales will not stop any time soon as so many incompetent boat owners know how to wreck the most unbreakable types of batteries in the market

I should have bought into battery shares I would be mega rich now

hope that all helps the boat users out there

[dstraton]

Thanks, bouncycastle

[bouncycastle]

small more like big ERROR in post 95 and correction post no 105 reference using two AGM annual costs

the real figure come closer to $350 a year becuase the cost of two battery at $560 = $1120 cancells out the added advantage of the 1200 cucle life

I reality AGM battery can be got a cheaper than that figure $560 0n 200 amps hour types often with buying two or more 100 to 150 amp types and making them join in parrell


It why in most installations if i do AGM installation i prefer to do small size AGM and drive them hard in the 50% DOD often at 0.2c rates for short duration and just tell the owner to replace battery with another AGM more often .

It works well for users who seldom use the boats such as weekender cruising or sailing less frequently.

A lot of them change boats more often than they change the battery so AGM become the next users problem.

SEP Somebody elses problem

Regret errors but summer calls doing up so many costumer boats makes fast maths mistakes and a lot of stress from owners as per every year engine issues

hope that helps the boating community.