Techie Acer aspire 5540 5541 5542 5550 series laptop battery ratings : li-ion,10.8v / 11.1v, 4400mathe battery output voltage and ampere ratings may vary a little but it will work with 100% performance supports the following laptop models: aspire 2420 series aspire 2920 series aspire 2920-1a2g16mi aspire 2920-302g25mi aspire 2920-3a2g12mi aspire 2920-3a2g25mi aspire 2920-3a2g25mn aspire 2920-5a2g25mi aspire 2920-602g25mn aspire 2920-603g25mi aspire 2920-832g32mn aspire 2920z series aspire 2920z-2a2g16mi aspire 2920z-2a2g25mi aspire 2920z-3a2g12mi aspire 3620 series aspire 3620a aspire 3623nwxmi aspire 3623wxmi aspire 3628awxci aspire 3628nwxmi aspire 3628wxmi aspire 3640 aspire 3670 aspire 5540 series aspire 5541anwxmi aspire 5542anwxmi aspire 5550 series aspire 5552nwxmi aspire 5560 series aspire 5561awxmi aspire 5562wxmi aspire 5563wxmi aspire 5590 extensor 3100 extensor 4120 series extensor 4220 extensor 4420 extensor 4620 extensor 4620-4691 extensor 4620-6402 extensor 4620z extensor 4630 series extensor 4630-4658 extensor 4630-4682 extensor 4630-4791 extensor 4630-4922 extensor 4630g-642g32mn extensor 4630g-732g25 extensor 4630z travel mate 2420 series travel mate 2420a travel mate 2423wxci travel mate 2423wxmi travel mate 2424nwxmi travel mate 2424wxci travel mate 2424wxmi travel mate 2428awxmi travel mate 2440 series travel mate 2470 travel mate 3010 series travel mate 3240 series travel mate 3242nwxmi travel mate 3250 series travel mate 3280 series travel mate 3282nwxmi travel mate 3282wxmi travel mate 3284wxmi travel mate 3290 travel mate 3300 series travel mate 3302wxmi travel mate 3304wxmi travel mate 4320 travel mate 4520 travel mate 4720 travel mate 6231 series travel mate 6231-100508ci travel mate 6231-301g12 travel mate 6231-401g12mi travel mate 6252 travel mate 6252-100508mi travel mate 6291 series travel mate 6291-101g12 travel mate 6291-101g12mi travel mate 6291-101g16 travel mate 6291-3a1g12mi travel mate 6291-6059 travel mate 6291-6335 travel mate 6291-6753 travel mate 6292 series travel mate 6292-101g08 travel mate 6292-101g16mi travel mate 6292-101g16mn travel mate 6292-101g16n travel mate 6292-102g16n travel mate 6292-301g16mi travel mate 6292-301g16mn travel mate 6292-301g16n travel mate 6292-302g16 travel mate 6292-302g161mi travel mate 6292-302g16mi travel mate 6292-302g16mn travel mate 6292-302g16n travel mate 6292-5b2g16mi travel mate 6292-5b2g16mn travel mate 6292-602g16mn travel mate 6292-602g25mn travel mate 6292-602g25n travel mate 6292-603g32mi travel mate 6292-6059 travel mate 6292-6192 travel mate 6292-6359 travel mate 6292-6427 travel mate 6292-643g32mn travel mate 6292-6700 travel mate 6292-6843 travel mate 6292-6856 travel mate 6292-6982 travel mate 6292-702g25mn travel mate 6292-812g25mn travel mate 6292-832g25mn travel mate 6292-833g25n travel mate 6292-834g25mi travel mate 6292-834g25mn travel mate 6292-834g32mi travel mate 6292-932g25mn travel mate 6293-6311 travel mate 6492 series travel mate 6492-601g16n travel mate 6492-602g16mn travel mate 6492-702g25mn travel mate 6492-812g25mn travel mate 6492-832g25n travel mate 6493 series travel mate 6493-6054 travel mate 6493-6495 travel mate 6493-6899 travel mate 6493-863g32mn travel mate 6493-863g32n travel mate 6553 series travel mate 6593 series travel mate 6593-6121 travel mate 6593-6170 travel mate 6593-6462 travel mate 6593-6882 travel mate 6593-842g16n travel mate 6593-842g25mn travel mate 6593g-842g25mn travel mate 6593g-863g32n travel mate 6593g-944g32mn.compatible battery part numbers (p/ns) 934c2130f 934t2130f bt.00603.012 bt.00603.014 bt.00603.026 bt.00603.039 bt.00603.040 bt.00604.005 bt.00604.006 bt.00604.017 bt.00605.002 bt.00605.003 bt.00605.006 bt.00605.007 bt.00605.027 bt.00607.003 bt.00607.009 bt.00607.018 bt.00903.004 bt.00904.003 bt.00907.003 btp-amj1 btp-anj1 btp-aoj1 btp-apj1 btp-aqj1 btp-arj1 btp-as3620 btp-asj1 btp-b2j1 btp-bqj1 btp-tm6231 garda31 garda32 lc.btp01.010 lc.btp01.011 ms2180 ms2181 ms2204 ms2211 ms2229 ms2230 q20154 tm-2007a tm07a72 please check above battery part number (p/n) from the label of existing battery. Kindly match carefully battery image, battery part number (p/n) and laptop model, before purchase. Battery buying tips, kindly read carefully : 1. The new laptop batteries are not fully pre charged, you have to charge them in your laptop before you expect some or full backup from a new battery. 2. When a laptop is not working, some buyers assume that the battery replacement is required. Please be aware that the laptop works well directly through ac adaptor even if the battery is not installed. If this is not the case, please do not directly buy the battery unless your laptop works well with ac adaptor. 3. If your old battery is totally dead i.e. If the laptop gives zero backup with your old battery then, there may be two possibilities : (a) the old battery is dead and laptop is ok. In this case, only replacing the battery with new one, will solve the problem. For this, just install the new battery into laptop and allow 3-4 hours to get it fully charged. During this time, you may keep working on your laptop. (b) old battery is dead and the battery charging circuit inside laptop motherboard, is also dead. In this case, the new battery can be utilised only after you get the laptop motherboard repaired from any expert technician. If you have any similar laptop battery near you for checking, you may try using that battery to check if laptop charging circuit is able to charge any battery and if that battery gives some backup time even if it is 4-5 minutes. Please be informed that laptop batteries should not be allowed to remain fully discharged for long time. If allowed, they becomes dead and unusable. I hope the information given above, will help you reach proper buying decision.