Whats wrong with this 12 volt 100 aH Li Ion battery?

softdown
softdown Solar Expert Posts: 3,812 ✭✭✭✭
At $580 it is remarkably low in the lithium battery battlefield. I'm sure red flags are popping. But it might be OK - almost. This one has 263 sales and the seller has 100% positive feedback. The product is already in the US as well. That is pretty unique for a bargain basement price. 

Red flags:
At 14 lbs - that is half what others weigh. Also small and only 1 year warranty.
 "1 Year Warranty
Product Weight  - 14 lbs - 6 kg
Product Size - 12 x 9.5 x 3 in"
No low temp charging cut out. That is almost always the case with less expensive batteries. "Protected against over voltage, over charge, short circuit, over tempature, over discharge, over wattage and over power."
Serial connections go up to 36 volt. Most of us are at 48 volt I think. If they can do 36 volt one might think they would do the work to accommodate 48 volt?

It is interesting.

https://www.ebay.com/itm/Lithium-12v-100Ah-Rechargeable-Deep-Cycle-Battery-Home-Charger-BMS-Solar-RV-/173898399831
First Bank:16 180 watt Grape Solar with  FM80 controller and 3648 Inverter....Fullriver 8D AGM solar batteries. Second Bank/MacGyver Special: 10 165(?) watt BP Solar with Renogy MPPT 40A controller/ and Xantrex C-35 PWM controller/ and Morningstar PWM controller...Cotek 24V PSW inverter....forklift and diesel locomotive batteries

Comments

  • APetersen10
    APetersen10 Registered Users, Users Awaiting Email Confirmation Posts: 1
    Dakota Battery is selling there 12V 100 AH batteries for about $849, and $809 if you buy two or more.  That is the best deal that I have found from a quality seller.
  • softdown
    softdown Solar Expert Posts: 3,812 ✭✭✭✭
    I still think Battle Born is likely the better value: 
    10 Year Warranty and moderately priced ~$950 or so. 

    The cheap batteries never seem to have a freezing temp charging disengage. Which will destroy a lithium battery - charging when it is frozen. 

    The cells seem to still be good. The BMS? Could be a $10 unit or a $250 unit. For example Battle Born has 10AWG cables in it. A cheaper battery uses 14AWG for the same work. 

    People pay well over $1000 and get 5 year warranties. Why? 

    FWIW the seller above has batteries that weigh twice as much as the "featured" battery for another $100. The lighter battery could be of interest to a backpacker or climber. I was tripping over nasty dead falls today with almost nothing in my pack. Shiver me timbers! 

    Saving $100 on the BMS while discounting the price by $100. Bit sketchy once a person studies BMS. 

    It appears that BMS competition is picking up. Hopefully we can get a good one for about $50 pretty soon. Good ones seem to be at least $100 last I heard. For a 100 aH battery that requires robust copper cabling. The  price jumps for BMS for bigger discharge rates - a lot. 
    First Bank:16 180 watt Grape Solar with  FM80 controller and 3648 Inverter....Fullriver 8D AGM solar batteries. Second Bank/MacGyver Special: 10 165(?) watt BP Solar with Renogy MPPT 40A controller/ and Xantrex C-35 PWM controller/ and Morningstar PWM controller...Cotek 24V PSW inverter....forklift and diesel locomotive batteries
  • softdown
    softdown Solar Expert Posts: 3,812 ✭✭✭✭
    edited August 2020 #4
    Dakota Battery is selling there 12V 100 AH batteries for about $849, and $809 if you buy two or more.  That is the best deal that I have found from a quality seller.
    Cabela's is asking $1249 for that battery. It has an 11 year warranty. Looks good.

    Dakota's web site is asking $899. Where do you see $849? 
    Can they used in serial? Most can not.

    Dakota claims their batteries can be used at -20F! Now that is amazing. NA at Amazon. Why is that I wonder - referring to 100aH. 

    Amazon geniuses are interesting. Like this reviewer: " Hybrid AGM and Lithium battery system"

    What could possibly go wrong? 
    First Bank:16 180 watt Grape Solar with  FM80 controller and 3648 Inverter....Fullriver 8D AGM solar batteries. Second Bank/MacGyver Special: 10 165(?) watt BP Solar with Renogy MPPT 40A controller/ and Xantrex C-35 PWM controller/ and Morningstar PWM controller...Cotek 24V PSW inverter....forklift and diesel locomotive batteries
  • softdown
    softdown Solar Expert Posts: 3,812 ✭✭✭✭
    Do they know what they are doing though? Consider this from their web site; 

    Experience the Dakota Lithium Difference

    The DL 100Ah battery is built with Dakota Lithium's legendary LiFePO4 cells. 2,000+ recharge cycles (roughly 5 year lifespan at daily use) vs. 500 for other lithium batteries or lead acid.

    5 year lifespan with 11 year warranty? OK. I would actually expect 20 years from a properly maintained Li Ion battery bank - that was properly designed and used. 

    There may still be some BMW cells in Pennsylvania available. At "87%". If I needed batteries I might do that. Shipping is $350 though. Ouch. 

    First Bank:16 180 watt Grape Solar with  FM80 controller and 3648 Inverter....Fullriver 8D AGM solar batteries. Second Bank/MacGyver Special: 10 165(?) watt BP Solar with Renogy MPPT 40A controller/ and Xantrex C-35 PWM controller/ and Morningstar PWM controller...Cotek 24V PSW inverter....forklift and diesel locomotive batteries
  • RCinFLA
    RCinFLA Solar Expert Posts: 1,484 ✭✭✭✭
    edited August 2020 #6
    The thing you have to be careful about when buying 12v self contained LFP batteries and stacking them is their BMS MOSFET switch breakdown voltage rating.  Many cheaper batteries use 20 to 25 volt breakdown MOSFET's,  You should not be stacking them.

    If the battery spec's doesn't say they can be stacked by 2 or by 4 then likely they cannot.  Battleborn for example states stacking four is okay.

    It cost more money to put in higher breakdown voltage MOSFET's.and because they usually come with higher Rs they have to put more devices in parallel to achieve the required Rs to support the maximum continuous current.
  • softdown
    softdown Solar Expert Posts: 3,812 ✭✭✭✭
    Very few can run in serial. I find that quite odd. I mean, off grid solar really does exist. So do 24 volt RV systems. 
    First Bank:16 180 watt Grape Solar with  FM80 controller and 3648 Inverter....Fullriver 8D AGM solar batteries. Second Bank/MacGyver Special: 10 165(?) watt BP Solar with Renogy MPPT 40A controller/ and Xantrex C-35 PWM controller/ and Morningstar PWM controller...Cotek 24V PSW inverter....forklift and diesel locomotive batteries