VHF Batteries - Reference new issue black with LED. Question on lifespan.

Discussion in 'Weapons, Equipment & Rations' started by MrBane, Jun 21, 2011.

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  1. MrBane

    MrBane LE Moderator Reviewer Reviews Editor

    Hi guys,

    Everyone's knocked off for the day and I need to find out what the longest anyone has managed to get out of the new VHF batteries is? I clocked in fourteen hours continuous use and still two bars left before changing.

    Any higher bidders?

  2. we got told on tour that should get upto 20 hours and indeed we did get some close to that. that said, we found they were not as reliable as old green batteries and tended to become problematic in charging after such prolongued use, requiring them to be sent to bowman FRT in Bastion for reconditioning - and they werent in a state of deep discharge
  3. MrBane

    MrBane LE Moderator Reviewer Reviews Editor

    Lovely. Thanks mate, that's what I needed to know. :)
  4. I have had up to 18 hours on one of the new black ones in Jordan however, they tend to be very tempramental. Some sets wouldn't work with black batteries and only work with green! Others would work with some black and not others. We ended up physically checking every battery to each specific set to make sure each set had 3 batteries that worked on that particular set. Funny beasts they are!
  5. Yep we had similar dramas, additionally not sure if it was a certain batch of bcip 5.4 sets but the black batteries couldnt be used when in certain roles (356) as would fry them due to being 32v rather than 28v of the green batteries. Worth keeping an eye on to save yourself the headache we had
  6. They were on their way though.

    Over discharging of Li-Ion batteries leads to supersaturation of the Lithium Cobalt Oxide cathode within the battery (ie the studs bottome bit). Eventually this oxide breaks down and Lithium Oxide is formed, this is the irriversable aspect of 'deep discharge'. Small amounts of Lithium Oxide can 'drop away' and pose no drama, but too much casues the battery to no longer hold charge.

    Supersaturation is the state of exhaustion in the battery... think of it as the same state as you should be at the end of a PFT, with no further energy to give. The Lithium ions move freely between teh electrods and mix with the cobalt and carbon, but once Oxideised they are no longer able to move or bond.
  7. Would I be wrong in guessing you're an ED? I can honestly say I learned something there though, even if it did mostly go over my head
  8. Yes, you would... I am a CS Engr.

    Think about in this way.

    Lithium Cobalt Oxide is a free moving compound, able to move from anode to cathode allowing charging and discharging. It is lighter (despite having more 'parts') than Lithium Oxide.

    Lithium Oxide is a compound that can not move from anode to cathode, so can not play apart charging or discharging. When enough of it accumulates it is actually a hinderence to the Lithium Cobalt Oxides that are trying to participate in the charging and discharging of the cell.

    Hence a state of 'deep discharge' is where there is so much Lithium Oxide that what Lithium Cobalt Oxide remains can't do it's job. And as an added bonus will create Lithium Hydroxide when mixed with H2O (water).

    Everyday's a school day ;)
  9. The nights must just fly by!!!
  10. The initial test results were 23 hrs with a new battery at 1:7:16 use ratio, although they will do 16 hrs at 2:2:4. (Transmit/Receive/Standby in mins)

    The LED's on all operational batteries should not be less than green for operational batteries and amber for trg batteries as well, based on the li-ion degradation to original capacity so well explained by CF.

    They should not be able to go into deep discharge like the Mk1-3 batteries, as they have protected allocation of charge which the user cannot access to stop the user seeing the effects of deep discharge.

    I am interested in the issues of unreliability, and under what circumstances, as they have been through a considerable amount of development - any comments appreciated.
  11. we found many batteries were falling into one of two categories, one being that they would be run down to the last LED flashing and from that point despite no amount of coaxing - the ACCU would never manage to recharge them. the second being that they would appear to charge - usually as far as four out of five bars, (seldom the last bar) but would not power anything. ie the radios would either not power on at all or claim low battery.
    I could never put my finger on what was causing this, no amount of preaching/pleading to the lads of the Coy I was with to keep an eye on the batteries and not run them down so much helped. Though I know it was often the last thing on their mind.

    I suspected but could never say conclusively that it was due to them being run right down till the manpack powered itself off from lack of battery life. We ended up backloading to bastion well in excess of a hundred batteries from the Coy alone, nevermind the battlegroup. Incidently, as I alluded to in a previous post, the black batteries caused dramas with the PRC 355's when run in the PRC 356 role with the BCIP5.4 radios which didn't exist before with the BCIP 4F radios and didn't occur when using the old green batteries, though I was lead to believe that was more down to the radio's themselves rather than the batteries - supposedly less tollerance to voltage variations. Again I was never able to confirm this though I saw it happen countless times so had my theories. Would be interesting to hear how the Royals faired after they took over from us.
  12. CIS/IR

    I expect you to have written in excess of a hundred for your Coy alone.
  13. we did them in bulk, so yes, though from speaking to our techs end of tour, many/most of the kit never arrived with any paperwork - the Bn evidently deemed it unnecesary!
  14. Brilliant.
  15. Acid, did this get back to the IPT? I just spoke this morning to the PM for bcip 5.4 and he hadn't had that feedback yet.