Recent content by IonicBond

fenix-store
  1. I

    Quality 12V 7.2ah SLA Batteries, How bad do they suck?

    Ok, you want the very best in small sla? The one that started it all: Enersys / Hawker Cyclon spiral D-sized (approx) agm. (Even though today they use flat plates in their much larger consumer Odyssey agm line.) Pure-lead, not recycled lead. Ability to be hammered at 1C if you know what you...
  2. I

    Charging LiFePO4 batteries, algorithms

    In regards to degradation, the missing element documented, but not discussed is the amount of *time* spent at or near full charge. Time is more of a degrading factor than voltage - within reason, like limiting a higher-voltage charge to 3.6v max for CV. As the charts show, any charge set for a...
  3. I

    Test/review of Yucel Y12-6L 6V 12Ah (Lead-Acid PB)

    Thanks HKJ! Pretty much the expected behavior. Anyone duplicating this test with new batts, will see capacity increase over the first 5 cycles or so as the plates get additional formatting. Then a plateu, and the long gradual drop just from usage. CC/CV notes: For those employing the...
  4. I

    What causes pack fires? [unfused dead cells]

    The reason LiFeP04 cells are claimed to be fireproof is that iron-phosphate (the "FeP04") part of the lithium chemistry does not release oxygen molecules, hence no flame since it is missing the oxygen component to start. BUT, when abused, they will vent. Dramatically, just like their cousins...
  5. I

    Eneloop Pro's going bad

    I've got about 8 of the pros - I may treat them a bit more like the old conventional nimh's and see how they fare in a few years in regards to internal resistance. The classic "Every 10 cycles, be sure to discharge to 1v (or 0.9v singly), and recharge. I will also take just a *tad* off the top...
  6. I

    Battery temps when charging - Should I be worried?

    Actually you are doing ok with two nice chargers - but know this: Eneloops are low-impedance cells that can actually handle 1C charging (2000mah typical), even though they may get uncomfortably warm near the 1 hour mark. Nimh in general are exothermic, meaning it is *normal* for them to get...
  7. I

    What is a good, inexpensive charger for SLA batteries?

    Heh, I've tracked many automotive speed-chargers and found them not well suited for long-term maintenance. Oh, they'll charge the battery alright - but at voltages that differ wildly from the display / chemistry voltages (usually by about 0.7v!) where that can mean burning up a gel, or...
  8. I

    Rechargeable Lithium Battery Long Term Viability

    Not wise. If you are uncomfortable at 80-90F, so are the batteries, no matter the level of charge if you want the longest life from them. Also, being unattended at a vacation house is not wise either - heaven forbid there is a fire - even if not caused by the batteries, but something else, if...
  9. I

    2000 mah charging for NiMH ?

    Good point! Other than eneloops which you can trust right out of the box (unless counterfeit), to being near stated capacity - other, not so much. So do a normal charge / discharge capacity test, and base your C charging rates from that. The general idea is to charge with enough current, so...
  10. I

    Best technique to keep a second car battery charged onboard ?

    I have that Tecmate / Optimate TM500 DC-DC charger and recommend it for a maintenance purpose like this with a caveat. HOWEVER, the output is only 2A, which of course would mean a LONG time to drive around between a deep discharge from the main battery with the inverter. But I suppose if one...
  11. I

    What makes internal resistance go high

    What I see here is overcharge due to too small of a charging current to make the cell emit the EOC signal. Thus the charger relies on other methods such as temperature or voltage extremes, which are well past the dv signal and now the cell is cooking and getting resistive. Try a fresh set, but...
  12. I

    2000 mah charging for NiMH ?

    Technically, 1C charging is actually better per Eneloop and some other high quality manufacturers. BUT, that is only if you dig into their specs, which the average consumer is unlikely to find. Lesser quality nimh may not like 1C. Yes, they get warm during charge, but that is expected of an...
  13. I

    Reconditioning Pb, losing track of MgSO4 -- or it worked *too* well???

    Exactly! Sometimes we can forget when it is just more practical to start over afresh. I thought for sure you'd be Mr. LifePo4 by now, where _cy_ has been hanging out and teaching (awesome!) since 2012 or so on advrider...
  14. I

    Reconditioning Pb, losing track of MgSO4 -- or it worked *too* well???

    Heh, here I'll try to say it in the concise manner that Silverfox would, instead of my usual multi-page prose.. :) Epsom salt added to the electrolyte is a way to remove sulfation quickly, and make old batteries seem like new. Disregarding the physical damage to the internal lead structure...
  15. I

    Reconditioning Pb, losing track of MgSO4 -- or it worked *too* well???

    Slinkygen - no offense intended. You seem like you are seriously interested in how the chemical reactions of Pb batts work. The red-flag was raised because in the past - and even to this day with other chemistries - posts about reviving batteries with epsom salt or other magic elixers from...
See more

Latest posts

Top