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Discussion Starter #1
Hi Dennis,

It's a 50V system, charger, controller, motor so wiring the 32ea 3.3V Thundersky 100ah LiFePO4 batteris in series for 100V would pop things or running a controller continuously at 50% duty cycle is inefficient.

Anyway I remember Lee saying something about buddy pairing lithium's that there's a chance that if one cell shorts (without buddy pair fuses) a fire can happen (not good in a wooden boat). But have there been *any* recorded incidences of lithium batteries internally shorting? I can find lithium fires due to overcharging/discharging but don't see any shorted cells on the great god Google (unless I'm missing something). So unless there's a valid reason to keep all those 32 pesky buddy pair 60A fuses, I'll remove them (and put in a central 200A pack fuse). I also thought of installing #12 fusible link wire for the #8 buddy pair wire (two #8's in parallel for 100A). I need to bump up the current rating for a larger Etek-RT 48-72V I'm putting on.

Wikipedia says that fusible link wire is 4 sizes smaller than the wire it protects (but don't see any actual current rating "amps" specs on fusible link wire just this rule of thumb). Is there anyone that's buddy pairing T-Sky etc lithiums using a fuse per battery, does it make sense to do so?

Have a LiFePO4 day,
mark
www.reevadiy.org
>
> ------------------------------
>
> Message: 29
> Date: Wed, 29 Sep 2010 12:32:32 -0400
> From: Dennis Miles <[email protected]>
> Subject: Re: [EVDL] Parallel Fuses or just wire together? LiFePO4
> Buddy balancing
> To: Electric Vehicle Discussion List <[email protected]>
> Message-ID:
> <[email protected]>
> Content-Type: text/plain; charset="iso-8859-1"
>
> There are many solutions, some seem more reliable than others especially in
> a marine environment, any fuse holder with a slight amount of corrosion may
> blow the paralleled fuse followed immediately by itself. Batteries behave
> much better in series, so why not put all in a single series string,
> (Systems generally are better with more voltage and somewhat less current
> and besides) the controller translates the power efficiently into pulses and
> the motor inductance and the Diodes in the controller give a higher current
> in the motor than the batteries need to supply, and you would only need one
> fuse, The batteries are much more reliable in one series string, the only
> drawback is needing a higher voltage charger,or charge half the pack at a
> time but be careful to maintain balance.
> Regards,
> *Dennis Lee Miles* (Director) *E.V.T.I. inc*.
> *www.E-V-T-I-Inc.COM <http://www.e-v-t-i-inc.com/> *(Adviser)*
> EVTI-EVAEducation Chapter
> *
> Phone (863) 944 - 9913
> Initial demand (computed by extrapolating the reservations for GM Volt and
> Nissan Leaf,) shall exceed 200,000 vehicles in 2010 and 2011. However only
> 50,000 vehicles will be marketed, so a LARGE demand for Nice Newer
> Conversions is predicted!
> ==================================================================
>
>
Mark Hanson <[email protected]>wrote:
>
> >
> > PS, how about replacing all the 32 fuses with wires and have a middle 200A
> > pack fuse?
> >
> >
> >
> > From: [email protected]
> > To: [email protected]
> > Subject: Parallel Fuses? LiFePO4 Buddy balancing
> > Date: Wed, 29 Sep 2010 08:18:17 -0400
> >
> >
> >
> >
> > Hi,
> >
> > In my www.evalbum.com/2749 E-Cat I'm thinking of putting a larger Etek-RT
> > 2k rpm @ 48V motor on a Johnson 9.9hp outboard with a 16x16 prop instead of
> > the 8x8 Briggs outboard using 80A. So my current will be in the 120 - 140A
> > range and I have the Lee Hart recommended 60A dual buddy pair fuses on the
> > Thundersky 100ah batteries (to make 200ah pairs). I have 32 fuses for the
> > 32 cells in parallel pairs to make 16 x 3.3 = 52.8V @ 200ah total. So I
> > essentially have 120A worth of fusing and now need to bump them up for a
> > larger motor/prop. I have a clump of 60A fuses and was thinking of doubling
> > them up, another 32 60A fuses for 240A worth of fusing. I know generally
> > you don't want to parallel fuses but not sure why it wouldn't work in this
> > situation, if one fuse starts getting hot, increasing resistance, its' buddy
> > will start to see more current flow and balance? I know RayChem with PTC's
> > says you can parallel their PTC's which sounds like a similar application.
> >
> > Have a renewable energy day,
> > Mark
> > www.reevadiy.org
> >
> > --------------
> >
>
>
>
> --
> -------------- next part --------------
> An HTML attachment was scrubbed...
> URL: http://lists.sjsu.edu/mailman/private/ev/attachments/20100929/cada2433/attachment.html
>
>
> ------------------------------
>
> Message: 30
> Date: Wed, 29 Sep 2010 10:54:45 -0600
> From: Zeke Yewdall <[email protected].xxx>
> Subject: Re: [EVDL] Late 80's Toyota Pickups
> To: [email protected], Electric Vehicle Discussion List
> <[email protected]>
> Message-ID:
> <[email protected]>
> Content-Type: text/plain; charset="iso-8859-1"
>
> I believe that the '84-88 trucks are largely the same as the '89 - '94
> trucks except for the revised body style for the later ones, and the IFS on
> the 4wd ones after 1986. http://www.toyoland.com/trucks/tacoma-hilux.html has
> a bit of info on them including some payload information. Same engines, so
> the same adaptors should work. I think I've seen one or two conversions of
> them, but I can't recall exactly where right now.
>
> Z
>
> On Wed, Sep 29, 2010 at 10:12 AM, Dave Hymers <[email protected]> wrote:
>
> > I'm looking at a 1987 Toyota truck in Tucson. I can't find any '87's on
> > evalbum, lots of '90+
> >
> > Does anyone know if the pre-90s trucks make ok conversions ? (lead)
> > I'm attempting to find a listing of the GVW also, pretty tough to track
> > down
> > before seeing it..
> >
> > Thanks
> >
> > Dave
> > -------------- next part --------------
> > An HTML attachment was scrubbed...
> > URL:
> > http://lists.sjsu.edu/mailman/private/ev/attachments/20100929/c22b2663/attachment.html
> > _______________________________________________
> > | REPLYING: address your message to [email protected] only.
> > | Multiple-address or CCed messages may be rejected.
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> >
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>
> ------------------------------
>
> _______________________________________________
> [email protected]
> For general EVDL support, see http://evdl.org/help/
> For subscription options, see http://lists.sjsu.edu/mailman/listinfo/ev
>
>
>
> End of EV Digest, Vol 38, Issue 46
> **********************************

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·
Registered
Joined
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70 Posts
Discussion Starter #2
They sure can short spontaneously, I've had it happen with A123 cells.

However, with thunder sky cells you may not gain much benefit fusing
them individually. Internally they already consists of several pouch
cells connected in parallel, without fusing of course. Any one of the
pouch cells can develop an internal short and the rest of the cells
will dump their energy into it. So fusing between batteries will cut
the available energy in half but that may not prevent a fire....





On Thu, Sep 30, 2010 at 5:41 AM, Mark Hanson <[email protected]> wro=
te:
>
> Hi Dennis,
>
> It's a 50V system, charger, controller, motor so wiring the 32ea 3.3V Thu=
ndersky 100ah LiFePO4 batteris in series for 100V would pop things or runni=
ng a controller continuously at 50% duty cycle is inefficient.
>
> Anyway I remember Lee saying something about buddy pairing lithium's that=
there's a chance that if one cell shorts (without buddy pair fuses) a fire=
can happen (not good in a wooden boat). But have there been *any* recor=
ded incidences of lithium batteries internally shorting? I can find lith=
ium fires due to overcharging/discharging but don't see any shorted cells o=
n the great god Google (unless I'm missing something). So unless there's=
a valid reason to keep all those 32 pesky buddy pair 60A fuses, I'll remov=
e them (and put in a central 200A pack fuse). I also thought of installi=
ng #12 fusible link wire for the #8 buddy pair wire (two #8's in parallel f=
or 100A). I need to bump up the current rating for a larger Etek-RT 48-=
72V I'm putting on.
>
> Wikipedia says that fusible link wire is 4 sizes smaller than the wire it=
protects (but don't see any actual current rating "amps" specs on fusible =
link wire just this rule of thumb). Is there anyone that's buddy pairing=
T-Sky etc lithiums using a fuse per battery, does it make sense to do so?
>
> Have a LiFePO4 day,
> mark
> www.reevadiy.org
>>
>> ------------------------------
>>
>> Message: 29
>> Date: Wed, 29 Sep 2010 12:32:32 -0400
>> From: Dennis Miles <[email protected]>
>> Subject: Re: [EVDL] Parallel Fuses or just wire together? LiFePO4
>> Buddy balancing
>> To: Electric Vehicle Discussion List <[email protected]>
>> Message-ID:
>> <[email protected]>
>> Content-Type: text/plain; charset=3D"iso-8859-1"
>>
>> There are many solutions, some seem more reliable than others especially=
in
>> a marine environment, any fuse holder with a slight amount of corrosion =
may
>> blow the paralleled fuse followed immediately by itself. Batteries behave
>> much better in series, so why not put all in a single series string,
>> (Systems generally are better with more voltage and somewhat less current
>> and besides) the controller translates the power efficiently into pulses=
and
>> the motor inductance and the Diodes in the controller give a higher curr=
ent
>> in the motor than the batteries need to supply, and you would only need =
one
>> fuse, The batteries are much more reliable in one series string, the only
>> drawback is needing a higher voltage charger,or charge half the pack at a
>> time but be careful to maintain balance.
>> Regards,
>> *Dennis Lee Miles* (Director) *E.V.T.I. inc*.
>> *www.E-V-T-I-Inc.COM <http://www.e-v-t-i-inc.com/> *(Adviser)*
>> EVTI-EVAEducation Chapter
>> *
>> Phone (863) 944 - 9913
>> Initial demand (computed by extrapolating the reservations for GM Volt a=
nd
>> Nissan Leaf,) shall exceed 200,000 vehicles in 2010 and 2011. However on=
ly
>> 50,000 vehicles will be marketed, so a LARGE demand for Nice Newer
>> Conversions is predicted!
>> =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
>>
>> On Wed, Sep 29, 2010 at 10:14 AM, Mark Hanson <[email protected]>=
wrote:
>>
>> >
>> > PS, how about replacing all the 32 fuses with wires and have a middle =
200A
>> > pack fuse?
>> >
>> >
>> >
>> > From: [email protected]
>> > To: [email protected]
>> > Subject: Parallel Fuses? LiFePO4 Buddy balancing
>> > Date: Wed, 29 Sep 2010 08:18:17 -0400
>> >
>> >
>> >
>> >
>> > Hi,
>> >
>> > In my www.evalbum.com/2749 E-Cat I'm thinking of putting a larger Etek=
-RT
>> > 2k rpm @ 48V motor on a Johnson 9.9hp outboard with a 16x16 prop inste=
ad of
>> > the 8x8 Briggs outboard using 80A. So my current will be in the 120 - =
140A
>> > range and I have the Lee Hart recommended 60A dual buddy pair fuses on=
the
>> > Thundersky 100ah batteries (to make 200ah pairs). I have 32 fuses for =
the
>> > 32 cells in parallel pairs to make 16 x 3.3 =3D 52.8V @ 200ah total. S=
o I
>> > essentially have 120A worth of fusing and now need to bump them up for=
a
>> > larger motor/prop. I have a clump of 60A fuses and was thinking of dou=
bling
>> > them up, another 32 60A fuses for 240A worth of fusing. I know general=
ly
>> > you don't want to parallel fuses but not sure why it wouldn't work in =
this
>> > situation, if one fuse starts getting hot, increasing resistance, its'=
buddy
>> > will start to see more current flow and balance? I know RayChem with P=
TC's
>> > says you can parallel their PTC's which sounds like a similar applicat=
ion.
>> >
>> > Have a renewable energy day,
>> > Mark
>> > www.reevadiy.org
>> >
>> > --------------
>> >
>>
>>
>>
>> --
>> -------------- next part --------------
>> An HTML attachment was scrubbed...
>> URL: http://lists.sjsu.edu/mailman/private/ev/attachments/20100929/cada2=
433/attachment.html
>>
>>
>> ------------------------------
>>
>> Message: 30
>> Date: Wed, 29 Sep 2010 10:54:45 -0600
>> From: Zeke Yewdall <[email protected]>
>> Subject: Re: [EVDL] Late 80's Toyota Pickups
>> To: [email protected], Electric Vehicle Discussion List
>> <[email protected]>
>> Message-ID:
>> <[email protected]>
>> Content-Type: text/plain; charset=3D"iso-8859-1"
>>
>> I believe that the '84-88 trucks are largely the same as the '89 - '94
>> trucks except for the revised body style for the later ones, and the IFS=
on
>> the 4wd ones after 1986. http://www.toyoland.com/trucks/tacoma-hilux.htm=
l has
>> a bit of info on them including some payload information. Same engines, =
so
>> the same adaptors should work. I think I've seen one or two conversions =
of
>> them, but I can't recall exactly where right now.
>>
>> Z
>>
>>
Dave Hymers <[email protected]> wrote:
>>
>> > I'm looking at a 1987 Toyota truck in Tucson. I can't find any '87's on
>> > evalbum, lots of '90+
>> >
>> > Does anyone know if the pre-90s trucks make ok conversions ? (lead)
>> > I'm attempting to find a listing of the GVW also, pretty tough to track
>> > down
>> > before seeing it..
>> >
>> > Thanks
>> >
>> > Dave
>> > -------------- next part --------------
>> > An HTML attachment was scrubbed...
>> > URL:
>> > http://lists.sjsu.edu/mailman/private/ev/attachments/20100929/c22b2663=
/attachment.html
>> > _______________________________________________
>> > | REPLYING: address your message to [email protected] only.
>> > | Multiple-address or CCed messages may be rejected.
>> > | UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
>> > | OTHER HELP: http://evdl.org/help/
>> > | OPTIONS: http://lists.sjsu.edu/mailman/listinfo/ev
>> >
>> -------------- next part --------------
>> An HTML attachment was scrubbed...
>> URL: http://lists.sjsu.edu/mailman/private/ev/attachments/20100929/0a15b=
7ea/attachment.html
>>
>>
>> ------------------------------
>>
>> _______________________________________________
>> [email protected]
>> For general EVDL support, see http://evdl.org/help/
>> For subscription options, see http://lists.sjsu.edu/mailman/listinfo/ev
>>
>>
>>
>> End of EV Digest, Vol 38, Issue 46
>> **********************************
>
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> | Multiple-address or CCed messages may be rejected.
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>



-- =

www.electric-lemon.com

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·
Registered
Joined
·
70 Posts
Discussion Starter #3
Mark,I see your point, However, I have never been a proponent of
parallel batteries.
I would build two series strings, and use one at time or put two
"Steering" diodes at one end as a combiner so both can supply but one cannot
back current into the weaker half pack.
It is a technique we have used before with success on a 24 v. lead acid
system. in an RV.
Regards,
*Dennis Lee Miles* (Director) *E.V.T.I. inc*.
*www.E-V-T-I-Inc.COM <http://www.e-v-t-i-inc.com/> *(Adviser)*
EVTI-EVAEducation Chapter
*
Phone (863) 944 - 9913
Initial demand (computed by extrapolating the reservations for GM Volt and
Nissan Leaf,) shall exceed 200,000 vehicles in 2010 and 2011. However only
50,000 vehicles will be marketed, so a LARGE demand for Nice Newer
Conversions is predicted!
-------------------------------------------------------------------------------------------------------------------------
Mark Hanson <[email protected]>wrote:

>
> Hi Dennis,
>
> It's a 50V system, charger, controller, motor so wiring the 32ea 3.3V
> Thundersky 100ah LiFePO4 batteris in series for 100V would pop things or
> running a controller continuously at 50% duty cycle is inefficient.
>
> Anyway I remember Lee saying something about buddy pairing lithium's that
> there's a chance that if one cell shorts (without buddy pair fuses) a fire
> can happen (not good in a wooden boat). But have there been *any* recorded
> incidences of lithium batteries internally shorting? I can find lithium
> fires due to overcharging/discharging but don't see any shorted cells on the
> great god Google (unless I'm missing something). So unless there's a valid
> reason to keep all those 32 pesky buddy pair 60A fuses, I'll remove them
> (and put in a central 200A pack fuse). I also thought of installing #12
> fusible link wire for the #8 buddy pair wire (two #8's in parallel for
> 100A). I need to bump up the current rating for a larger Etek-RT 48-72V
> I'm putting on.
>
> Wikipedia says that fusible link wire is 4 sizes smaller than the wire it
> protects (but don't see any actual current rating "amps" specs on fusible
> link wire just this rule of thumb). Is there anyone that's buddy pairing
> T-Sky etc lithiums using a fuse per battery, does it make sense to do so?
>
> Have a LiFePO4 day,
> mark
> www.reevadiy.org
> >
> > ------------------------------
> >
> > Message: 29
> > Date: Wed, 29 Sep 2010 12:32:32 -0400
> > From: Dennis Miles <[email protected]>
> > Subject: Re: [EVDL] Parallel Fuses or just wire together? LiFePO4
> > Buddy balancing
> > To: Electric Vehicle Discussion List <[email protected]>
> > Message-ID:
> > <[email protected]>
> > Content-Type: text/plain; charset="iso-8859-1"
> >
> > There are many solutions, some seem more reliable than others especially
> in
> > a marine environment, any fuse holder with a slight amount of corrosion
> may
> > blow the paralleled fuse followed immediately by itself. Batteries behave
> > much better in series, so why not put all in a single series string,
> > (Systems generally are better with more voltage and somewhat less current
> > and besides) the controller translates the power efficiently into pulses
> and
> > the motor inductance and the Diodes in the controller give a higher
> current
> > in the motor than the batteries need to supply, and you would only need
> one
> > fuse, The batteries are much more reliable in one series string, the only
> > drawback is needing a higher voltage charger,or charge half the pack at a
> > time but be careful to maintain balance.
> > Regards,
> > *Dennis Lee Miles* (Director) *E.V.T.I. inc*.
> > *www.E-V-T-I-Inc.COM <http://www.e-v-t-i-inc.com/> *(Adviser)*
> > EVTI-EVAEducation Chapter
> > *
> > Phone (863) 944 - 9913
> > Initial demand (computed by extrapolating the reservations for GM Volt
> and
> > Nissan Leaf,) shall exceed 200,000 vehicles in 2010 and 2011. However
> only
> > 50,000 vehicles will be marketed, so a LARGE demand for Nice Newer
> > Conversions is predicted!
> > ==================================================================
> >
> > On Wed, Sep 29, 2010 at 10:14 AM, Mark Hanson <[email protected]
> >wrote:
> >
> > >
> > > PS, how about replacing all the 32 fuses with wires and have a middle
> 200A
> > > pack fuse?
> > >
> > >
> > >
> > > From: [email protected]
> > > To: [email protected]
> > > Subject: Parallel Fuses? LiFePO4 Buddy balancing
> > > Date: Wed, 29 Sep 2010 08:18:17 -0400
> > >
> > >
> > >
> > >
> > > Hi,
> > >
> > > In my www.evalbum.com/2749 E-Cat I'm thinking of putting a larger
> Etek-RT
> > > 2k rpm @ 48V motor on a Johnson 9.9hp outboard with a 16x16 prop
> instead of
> > > the 8x8 Briggs outboard using 80A. So my current will be in the 120 -
> 140A
> > > range and I have the Lee Hart recommended 60A dual buddy pair fuses on
> the
> > > Thundersky 100ah batteries (to make 200ah pairs). I have 32 fuses for
> the
> > > 32 cells in parallel pairs to make 16 x 3.3 = 52.8V @ 200ah total. So I
> > > essentially have 120A worth of fusing and now need to bump them up for
> a
> > > larger motor/prop. I have a clump of 60A fuses and was thinking of
> doubling
> > > them up, another 32 60A fuses for 240A worth of fusing. I know
> generally
> > > you don't want to parallel fuses but not sure why it wouldn't work in
> this
> > > situation, if one fuse starts getting hot, increasing resistance, its'
> buddy
> > > will start to see more current flow and balance? I know RayChem with
> PTC's
> > > says you can parallel their PTC's which sounds like a similar
> application.
> > >
> > > Have a renewable energy day,
> > > Mark
> > > www.reevadiy.org
> > >
> > > --------------
> > >
> >
> >
> >
> > --
> > -------------- next part --------------
> > An HTML attachment was scrubbed...
> > URL:
> http://lists.sjsu.edu/mailman/private/ev/attachments/20100929/cada2433/attachment.html
> >
> >
> > ------------------------------
> >
> > Message: 30
> > Date: Wed, 29 Sep 2010 10:54:45 -0600
> > From: Zeke Yewdall <[email protected]>
> > Subject: Re: [EVDL] Late 80's Toyota Pickups
> > To: [email protected], Electric Vehicle Discussion List
> > <[email protected]>
> > Message-ID:
> > <[email protected]>
> > Content-Type: text/plain; charset="iso-8859-1"
> >
> > I believe that the '84-88 trucks are largely the same as the '89 - '94
> > trucks except for the revised body style for the later ones, and the IFS
> on
> > the 4wd ones after 1986.
> http://www.toyoland.com/trucks/tacoma-hilux.html has
> > a bit of info on them including some payload information. Same engines,
> so
> > the same adaptors should work. I think I've seen one or two conversions
> of
> > them, but I can't recall exactly where right now.
> >
> > Z
> >
> > On Wed, Sep 29, 2010 at 10:12 AM, Dave Hymers <[email protected]> wrote:
> >
> > > I'm looking at a 1987 Toyota truck in Tucson. I can't find any '87's on
> > > evalbum, lots of '90+
> > >
> > > Does anyone know if the pre-90s trucks make ok conversions ? (lead)
> > > I'm attempting to find a listing of the GVW also, pretty tough to track
> > > down
> > > before seeing it..
> > >
> > > Thanks
> > >
> > > Dave
> > > -------------- next part --------------
> > > An HTML attachment was scrubbed...
> > > URL:
> > >
> http://lists.sjsu.edu/mailman/private/ev/attachments/20100929/c22b2663/attachment.html
> > > _______________________________________________
> > > | REPLYING: address your message to [email protected] only.
> > > | Multiple-address or CCed messages may be rejected.
> > > | UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub
> > > | OTHER HELP: http://evdl.org/help/
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> > >
> > -------------- next part --------------
> > An HTML attachment was scrubbed...
> > URL:
> http://lists.sjsu.edu/mailman/private/ev/attachments/20100929/0a15b7ea/attachment.html
> >
> >
> > ------------------------------
> >
> > _______________________________________________
> > [email protected]
> > For general EVDL support, see http://evdl.org/help/
> > For subscription options, see http://lists.sjsu.edu/mailman/listinfo/ev
> >
> >
> >
> > End of EV Digest, Vol 38, Issue 46
> > **********************************
>
> -------------- next part --------------
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Discussion Starter #4
Dennis Miles <[email protected]> wrote:

> Mark,I see your point, However, I have never been a proponent of
> parallel batteries.
> I would build two series strings, and use one at time or put two
> "Steering" diodes at one end as a combiner so both can supply but one
> cannot
> back current into the weaker half pack.
> It is a technique we have used before with success on a 24 v. lead acid
> system. in an RV.
>
>
That works for discharging, but also prevents charging the batteries....
you'd need a different set of leads, with steering diodes going the other
way, that you hooked up when you wanted to charge the batteries.

Z
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Discussion Starter #5
Dennis Miles <[email protected]> wrote:
> Mark,I see your point, However, I have never been a proponent of
> parallel batteries.
> I would build two series strings, and use one at time or put t=
wo
> "Steering" diodes at one end as a combiner so both can supply but one can=
not
> back current into the weaker half pack.
> It is a technique we have used before with success on a 24 v. lea=
d acid
> system. in an RV.

But remember that LiFePO4 is quite different than lead acid. Other
than the extra external connection what really is the difference in
connecting two 100Ah cells or one 200Ah cell? Both will have the same
plate surface area and so have the same probability of an internal
short. The charge/discharge curves of LFP is ideal for parallel
setups. In the discharge-rest tests graphs I've seen the voltage
always drops on discharge. Weaker cells have a greater voltage drop so
even if you were to parallel a 100Ah with a 40Ah cell they both would
put out the same or nearly the same C rate. I don't have the equipment
to prove this but I would if I had it. With two slightly different
100Ah cells the weaker one would put out a slightly lower C rate than
the stronger one. From the info I've been gleaning about battery life
the one stressed more will decline faster than the other one. It
appears that in a short while the two cells will pull together. This
next summer I'm planning on pulling my 2P20S TS-LFP100AHA pack apart
an checking out how closely the cell pairs are matched. I assembled
them by matching a higher capacity with a lower capacity cell to try
to get all the cell pairs roughly the same. I have over 4000 miles and
over 9000Ah on the pack at this point.


-- =

David D. Nelson
http://evalbum.com/1328

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